Constitutive activation of integrin αvβ3 contributes to anoikis resistance of ovarian cancer cells

Epithelial ovarian cancer involves the shedding of single tumor cells or spheroids from the primary tumor into ascites, followed by their survival, and transit to the sites of metastatic colonization within the peritoneal cavity. During their flotation, anchorage‐dependent epithelial‐type tumor cells gain anoikis resistance, implicating integrins, including αvß3. In this study, we explored anoikis escape, cisplatin resistance, and prosurvival signaling as a function of the αvß3 transmembrane conformational activation state in cells suspended in ascites. A high‐affinity and constitutively signaling‐competent αvß3 variant, which harbored unclasped transmembrane domains, was found to confer delayed anoikis onset, enhanced cisplatin resistance, and reduced cell proliferation in ascites or 3D‐hydrogels, involving p27^kip upregulation. Moreover, it promoted EGF‐R expression and activation, prosurvival signaling, implicating FAK, src, and PKB/Akt. This led to the induction of the anti‐apoptotic factors Bcl‐2 and survivin suppressing caspase activation, compared to a signaling‐incapable αvß3 variant displaying firmly associated transmembrane domains. Dissecting the mechanistic players for αvß3‐dependent survival and peritoneal metastasis of ascitic ovarian cancer spheroids is of paramount importance to target their anchorage independence by reversing anoikis resistance and blocking αvß3‐triggered prosurvival signaling.

Abbreviations

CLSM

confocal laser scanning microscopy

ECM

extracellular matrix

EGF‐R

epidermal growth factor receptor

EOC

epithelial ovarian cancer

FAK

focal adhesion kinase

FIGO

Fédération Internationale de Gynécologie et d''Obstétrique

GAPDH

glyceraldehyde 3‐phosphate dehydrogenase)

GpA

glycophorin A

IMD

integrin‐mediated death

MAPK

mitogen‐activated protein kinases

PI

propidium iodide

RGD

Arg‐Gly‐Asp

TMD

transmembrane domain

     

SMARCA4 mutations in KRAS‐mutant lung adenocarcinoma: a multi‐cohort analysis

KRAS is a key oncogenic driver in lung adenocarcinoma (LUAD). Chromatin‐remodeling gene SMARCA4 is comutated with KRAS in LUAD; however, the impact of SMARCA4 mutations on clinical outcome has not been adequately established. This study sought to shed light on the clinical significance of SMARCA4 mutations in LUAD. The association of SMARCA4 mutations with survival outcomes was interrogated in four independent cohorts totaling 564 patients: KRAS‐mutant patients with LUAD who received nonimmunotherapy treatment from (a) The Cancer Genome Atlas (TCGA) and (b) the MSK‐IMPACT Clinical Sequencing (MSK‐CT) cohorts; and KRAS‐mutant patients with LUAD who received immune checkpoint inhibitor‐based immunotherapy treatment from (c) the MSK‐IMPACT (MSK‐IO) and (d) the Wake Forest Baptist Comprehensive Cancer Center (WFBCCC) immunotherapy cohorts. Of the patients receiving nonimmunotherapy treatment, in the TCGA cohort (n = 155), KRAS‐mutant patients harboring SMARCA4 mutations (KS) showed poorer clinical outcome [P = 6e‐04 for disease‐free survival (DFS) and 0.031 for overall survival (OS), respectively], compared to KRAS‐TP53 comutant (KP) and KRAS‐only mutant (K) patients; in the MSK‐CT cohort (n = 314), KS patients also exhibited shorter OS than KP (P = 0.03) or K (P = 0.022) patients. Of patients receiving immunotherapy, KS patients consistently exhibited the shortest progression‐free survival (PFS; P = 0.0091) in the MSK‐IO (n = 77), and the shortest PFS (P = 0.0026) and OS (P = 0.0014) in the WFBCCC (n = 18) cohorts, respectively. Therefore, mutations of SMARCA4 represent a genetic factor leading to adverse clinical outcome in lung adenocarcinoma treated by either nonimmunotherapy or immunotherapy.

Abbreviations

DCB

durable clinical benefit

DFS

disease‐free survival

K

KRAS‐only mutant

KL

KRAS‐STK11 comutant

KP

KRAS‐TP53 comutant

KS

KRAS‐SMARCA4 comutant

LUAD

lung adenocarcinoma

LUSC

lung squamous carcinoma

MSK‐CT

the MSK‐IMPACT clinical sequencing cohort

MSK‐IO

MSK‐IMPACT cohort

NSCLC

non‐small‐cell lung cancer

OS

overall survival

PFS

progression‐free survival

TCGA

The Cancer Genome Atlas

WFBCCC

the Wake Forest Baptist Comprehensive Cancer Center

     

Downregulation of Glutamine Synthetase,not glutaminolysis,is responsible for glutamine addiction in Notch1‐driven acute lymphoblastic leukemia

The cellular receptor Notch1 is a central regulator of T‐cell development, and as a consequence, Notch1 pathway appears upregulated in > 65% of the cases of T‐cell acute lymphoblastic leukemia (T‐ALL). However, strategies targeting Notch1 signaling render only modest results in the clinic due to treatment resistance and severe side effects. While many investigations reported the different aspects of tumor cell growth and leukemia progression controlled by Notch1, less is known regarding the modifications of cellular metabolism induced by Notch1 upregulation in T‐ALL. Previously, glutaminolysis inhibition has been proposed to synergize with anti‐Notch therapies in T‐ALL models. In this work, we report that Notch1 upregulation in T‐ALL induced a change in the metabolism of the important amino acid glutamine, preventing glutamine synthesis through the downregulation of glutamine synthetase (GS). Downregulation of GS was responsible for glutamine addiction in Notch1‐driven T‐ALL both in vitro and in vivo. Our results also confirmed an increase in glutaminolysis mediated by Notch1. Increased glutaminolysis resulted in the activation of the mammalian target of rapamycin complex 1 (mTORC1) pathway, a central controller of cell growth. However, glutaminolysis did not play any role in Notch1‐induced glutamine addiction. Finally, the combined treatment targeting mTORC1 and limiting glutamine availability had a synergistic effect to induce apoptosis and to prevent Notch1‐driven leukemia progression. Our results placed glutamine limitation and mTORC1 inhibition as a potential therapy against Notch1‐driven leukemia.

Abbreviations

7‐AAD

7‐Aminoactinomycin D

BPTES

bis‐2‐(5‐phenylacetamido‐1,2,4‐thiadiazol‐2‐yl)ethyl sulfide

DON

diazo‐5‐oxo‐L‐norleucine

ECAR

extracellular acidification rate

GDH

glutamate dehydrogenase

GLS

glutaminase

GS

glutamine synthetase

GSI

γ‐secretase inhibitor

MSO

L‐methionine sulfoximine

mTORC1

mammalian target of rapamycin complex 1

NICD

Notch intracellular domain

PI

propidium iodide

RAP

rapamycin

T‐ALL

T‐cell acute lymphoblastic leukemia

TCA

tricarboxylic acid

αKG

α‐ketoglutarate

     

Comprehensive cross‐platform comparison of methods for non‐invasive EGFR mutation testing: results of the RING observational trial

Several platforms for noninvasive EGFR testing are currently used in the clinical setting with sensitivities ranging from 30% to 100%. Prospective studies evaluating agreement and sources for discordant results remain lacking. Herein, seven methodologies including two next‐generation sequencing (NGS)‐based methods, three high‐sensitivity PCR‐based platforms, and two FDA‐approved methods were compared using 72 plasma samples, from EGFR‐mutant non‐small‐cell lung cancer (NSCLC) patients progressing on a first‐line tyrosine kinase inhibitor (TKI). NGS platforms as well as high‐sensitivity PCR‐based methodologies showed excellent agreement for EGFR‐sensitizing mutations (K = 0.80–0.89) and substantial agreement for T790M testing (K = 0.77 and 0.68, respectively). Mutant allele frequencies (MAFs) obtained by different quantitative methods showed an excellent reproducibility (intraclass correlation coefficients 0.86–0.98). Among other technical factors, discordant calls mostly occurred at mutant allele frequencies (MAFs) ≤ 0.5%. Agreement significantly improved when discarding samples with MAF ≤ 0.5%. EGFR mutations were detected at significantly lower MAFs in patients with brain metastases, suggesting that these patients risk for a false‐positive result. Our results support the use of liquid biopsies for noninvasive EGFR testing and highlight the need to systematically report MAFs.

Abbreviations

BEAMing

beads, emulsion, amplification, and magnetics

cfDNA

circulating free DNA, cell‐free DNA

cobas

cobas^® EGFR Mutation Test v2 (Roche Diagnostics)

ctDNA

circulating tumor DNA

CUSUM

cumulative sum

ddPCR

droplet digital polymerase chain reaction

dPCR

digital polymerase chain reaction

EGFR

epidermal growth factor receptor

FFPE

formalin‐fixed, paraffin‐embedded

ICC

intraclass correlation coefficient

MAF

mutant allele frequency

NGS platforms

Ion S5™ XL and GeneRead™

NGS

next‐generation sequencing

NSCLC

non‐small‐cell lung cancer

PNA‐Q‐PCR

peptic nucleic acid probe‐based real‐time polymerase chain reaction

Therascreen

Therascreen EGFR Plasma RGQ PCR Kit (QIAgen)

TKI

tyrosine kinase inhibitor

     

Long noncoding RNA LINC01578 drives colon cancer metastasis through a positive feedback loop with the NF‐κB/YY1 axis

Metastasis accounts for poor prognosis of cancers and related deaths. Accumulating evidence has shown that long noncoding RNAs (lncRNAs) play critical roles in several types of cancer. However, which lncRNAs contribute to metastasis of colon cancer is still largely unknown. In this study, we found that lncRNA LINC01578 was correlated with metastasis and poor prognosis of colon cancer. LINC01578 was upregulated in colon cancer, associated with metastasis, advanced clinical stages, poor overall survival, disease‐specific survival, and disease‐free survival. Gain‐of‐function and loss‐of‐function assays revealed that LINC01578 enhanced colon cancer cell viability and mobility in vitro and colon cancer liver metastasis in vivo. Mechanistically, nuclear factor kappa B (NF‐κB) and Yin Yang 1 (YY1) directly bound to the LINC01578 promoter, enhanced its activity, and activated LINC01578 expression. LINC01578 was shown to be a chromatin‐bound lncRNA, which directly bound NFKBIB promoter. Furthermore, LINC01578 interacted with and recruited EZH2 to NFKBIB promoter and further repressed NFKBIB expression, thereby activating NF‐κB signaling. Through activation of NF‐κB, LINC01578 further upregulated YY1 expression. Through activation of the NF‐κB/YY1 axis, LINC01578 in turn enhanced its own promoter activity, suggesting that LINC01578 and NF‐κB/YY1 formed a positive feedback loop. Blocking NF‐κB signaling abolished the oncogenic roles of LINC01578 in colon cancer. Furthermore, the expression levels of LINC01578, NFKBIB, and YY1 were correlated in clinical tissues. Collectively, this study demonstrated that LINC01578 promoted colon cancer metastasis via forming a positive feedback loop with NF‐κB/YY1 and suggested that LINC01578 represents a potential prognostic biomarker and therapeutic target for colon cancer metastasis.

Abbreviations

ChIP

chromatin immunoprecipitation

ChIRP

chromatin isolation by RNA purification

COAD

colon adenocarcinoma

CPAT

Coding‐Potential Assessment Tool

CPC

coding potential calculator

DFS

disease‐free survival

DSS

disease‐specific survival

EdU

5‐ethynyl‐2''‐deoxyuridine

H&E

hematoxylin and eosin

HR

hazard ratio

IHC

immunohistochemistry

IKK

IκB kinase

IκB

inhibitory κB

lncRNAs

long noncoding RNAs

NC

negative control

NCBI

National Center for Biotechnology Information

NF‐κB

nuclear factor kappa B

qRT‐PCR

quantitative real‐time polymerase chain reaction

RIP

RNA immunoprecipitation

RPISeq

RNA‐Protein Interaction Prediction

TCGA

The Cancer Genome Atlas

TNF

tumor necrosis factor

TUNEL

TdT‐mediated dUTP Nick‐End Labeling

YY1

Yin Yang 1

     

In silico molecular target prediction unveils mebendazole as a potent MAPK14 inhibitor

The concept of polypharmacology involves the interaction of drug molecules with multiple molecular targets. It provides a unique opportunity for the repurposing of already‐approved drugs to target key factors involved in human diseases. Herein, we used an in silico target prediction algorithm to investigate the mechanism of action of mebendazole, an antihelminthic drug, currently repurposed in the treatment of brain tumors. First, we confirmed that mebendazole decreased the viability of glioblastoma cells in vitro (IC₅₀ values ranging from 288 nm to 2.1 µm). Our in silico approach unveiled 21 putative molecular targets for mebendazole, including 12 proteins significantly upregulated at the gene level in glioblastoma as compared to normal brain tissue (fold change > 1.5; P < 0.0001). Validation experiments were performed on three major kinases involved in cancer biology: ABL1, MAPK1/ERK2, and MAPK14/p38α. Mebendazole could inhibit the activity of these kinases in vitro in a dose‐dependent manner, with a high potency against MAPK14 (IC₅₀ = 104 ± 46 nm). Its direct binding to MAPK14 was further validated in vitro, and inhibition of MAPK14 kinase activity was confirmed in live glioblastoma cells. Consistent with biophysical data, molecular modeling suggested that mebendazole was able to bind to the catalytic site of MAPK14. Finally, gene silencing demonstrated that MAPK14 is involved in glioblastoma tumor spheroid growth and response to mebendazole treatment. This study thus highlighted the role of MAPK14 in the anticancer mechanism of action of mebendazole and provides further rationale for the pharmacological targeting of MAPK14 in brain tumors. It also opens new avenues for the development of novel MAPK14/p38α inhibitors to treat human diseases.

Abbreviations

BRET

bioluminescence resonance energy transfer

GBM

glioblastoma

GTeX

Genotype‐Tissue Expression

IC₅₀

half‐maximal inhibitory concentration

ITC

isothermal titration calorimetry

MBZ

mebendazole

nanoDSF

nanoscale differential scanning fluorimetry

qRT‐PCR

quantitative real‐time polymerase chain reaction

RT

room temperature

siRNA

small interfering RNA

TCGA

The Cancer Genome Atlas

TSA

thermal shift assay

     

Circulating tumor cell detection and single‐cell analysis using an integrated workflow based on ChimeraX®‐i120 Platform: A prospective study

Circulating tumor cell (CTC) analysis holds great potential to be a noninvasive solution for clinical cancer management. A complete workflow that combined CTC detection and single‐cell molecular analysis is required. We developed the ChimeraX^®‐i120 platform to facilitate negative enrichment, immunofluorescent labeling, and machine learning‐based identification of CTCs. Analytical performances were evaluated, and a total of 477 participants were enrolled to validate the clinical feasibility of ChimeraX^®‐i120 CTC detection. We analyzed copy number alteration profiles of isolated single cells. The ChimeraX^®‐i120 platform had high sensitivity, accuracy, and reproducibility for CTC detection. In clinical samples, an average value of > 60% CTC‐positive rate was found for five cancer types (i.e., liver, biliary duct, breast, colorectal, and lung), while CTCs were rarely identified in blood from healthy donors. In hepatocellular carcinoma patients treated with curative resection, CTC status was significantly associated with tumor characteristics, prognosis, and treatment response (all P < 0.05). Single‐cell sequencing analysis revealed that heterogeneous genomic alteration patterns resided in different cells, patients, and cancers. Our results suggest that the use of this ChimeraX^®‐i120 platform and the integrated workflow has validity as a tool for CTC detection and downstream genomic profiling in the clinical setting.

Abbreviations

ADABOOST

AdaBoost classification trees

AFP

alpha‐fetoprotein

AUC

areas under the curve

BC

breast cancer

BCLC

barcelona clinic liver cancer

BHL

benign hepatic lesion

CCD

charge‐coupled device

CHB

chronic hepatitis B

CK

cytokeratin

CNA

copy number alteration

CNLC

Chinese staging for liver cancer

CRC

colorectal cancer

CTC

circulating tumor cell

CTM

circulating tumor microemboli

CV

coefficient of variation

DAPI

4’,6‐diamidine‐2’‐phenylindole dihydrochloride

EpCAM

epithelial cell adhesion molecule

FPR

false‐positive rate

GBM

stochastic gradient boosting

HCC

hepatocellular carcinoma

HD

healthy donor

ICC

intrahepatic cholangiocarcinoma

LC

liver cirrhosis

LCA

lung cancer

LOD

limit of detection

PBS

phosphate‐buffered saline

PCR

polymerase chain reaction

RF

random forest

ROC

receiver operating characteristic

SVM

support vector machines

TCGA

The Cancer Genome Atlas

TPR

true‐positive rate

TTR

time to recurrence

WBC

white blood cell

WGA

whole‐genome amplification

WGS

whole‐genome sequencing

XGB

extreme gradient boosting

     

Targeted inhibition of ERα signaling and PIP5K1α/Akt pathways in castration‐resistant prostate cancer

Selective ERα modulator, tamoxifen, is well tolerated in a heavily pretreated castration‐resistant prostate cancer (PCa) patient cohort. However, its targeted gene network and whether expression of intratumor ERα due to androgen deprivation therapy (ADT) may play a role in PCa progression is unknown. In this study, we examined the inhibitory effect of tamoxifen on castration‐resistant PCa in vitro and in vivo. We found that tamoxifen is a potent compound that induced a high degree of apoptosis and significantly suppressed growth of xenograft tumors in mice, at a degree comparable to ISA‐2011B, an inhibitor of PIP5K1α that acts upstream of PI3K/AKT survival signaling pathway. Moreover, depletion of tumor‐associated macrophages using clodronate in combination with tamoxifen increased inhibitory effect of tamoxifen on aggressive prostate tumors. We showed that both tamoxifen and ISA‐2011B exert their on‐target effects on prostate cancer cells by targeting cyclin D1 and PIP5K1α/AKT network and the interlinked estrogen signaling. Combination treatment using tamoxifen together with ISA‐2011B resulted in tumor regression and had superior inhibitory effect compared with that of tamoxifen or ISA‐2011B alone. We have identified sets of genes that are specifically targeted by tamoxifen, ISA‐2011B or combination of both agents by RNA‐seq. We discovered that alterations in unique gene signatures, in particular estrogen‐related marker genes are associated with poor patient disease‐free survival. We further showed that ERα interacted with PIP5K1α through formation of protein complexes in the nucleus, suggesting a functional link. Our finding is the first to suggest a new therapeutic potential to inhibit or utilize the mechanisms related to ERα, PIP5K1α/AKT network, and MMP9/VEGF signaling axis, providing a strategy to treat castration‐resistant ER‐positive subtype of prostate cancer tumors with metastatic potential.

Abbreviations

CRPC

castration‐resistant prostate cancer

DHT

dihydrotestosterone

E2

estradiol

ERα

estrogen receptor alpha

GO

gene ontology

NG‐CHM

Next‐Generation Clustered Heatmaps

PCa

prostate cancer

TMAs

tissue microarrays

     

Genomic and prognostic heterogeneity among RAS/BRAF V600E/TP53 co‐mutated resectable colorectal liver metastases

Hepatic resection is potentially curative for patients with colorectal liver metastases, but the treatment benefit varies. KRAS/NRAS (RAS)/TP53 co‐mutations are associated with a poor prognosis after resection, but there is large variation in patient outcome within the mutation groups, and genetic testing is currently not used to evaluate benefit from surgery. We have investigated the potential for improved prognostic stratification by combined biomarker analysis with DNA copy number aberrations (CNAs), and taking tumor heterogeneity into account. We determined the mutation status of RAS, BRAF ^V600, and TP53 in 441 liver lesions from 171 patients treated by partial hepatectomy for metastatic colorectal cancer. CNAs were profiled in 232 tumors from 67 of the patients. Mutations and high‐level amplifications of cancer‐critical genes, the latter including ERBB2 and EGFR, were predominantly homogeneous within patients. RAS/BRAF ^V600E and TP53 co‐mutations were associated with a poor patient outcome (hazard ratio, HR, 3.9, 95% confidence interval, CI, 1.3–11.1, P = 0.012) in multivariable analyses with clinicopathological variables. The genome‐wide CNA burden and intrapatient intermetastatic CNA heterogeneity varied within the mutation groups, and the CNA burden had prognostic associations in univariable analysis. Combined prognostic analyses of RAS/BRAF ^V600E/TP53 mutations and CNAs, either as a high CNA burden or high intermetastatic CNA heterogeneity, identified patients with a particularly poor outcome (co‐mutation/high CNA burden: HR 2.7, 95% CI 1.2–5.9, P = 0.013; co‐mutation/high CNA heterogeneity: HR 2.5, 95% CI 1.1–5.6, P = 0.022). In conclusion, DNA copy number profiling identified genomic and prognostic heterogeneity among patients with resectable colorectal liver metastases with co‐mutated RAS/BRAF ^V600E/TP53.

Abbreviations

5y‐CSS

five‐year cancer‐specific survival

CNA

copy number aberrations

CRC

colorectal cancer

CRLM

colorectal liver metastases

MSI

microsatellite instable

MSS

microsatellite stable

     

The genetic landscape of metaplastic breast cancers and uterine carcinosarcomas

Metaplastic breast carcinoma (MBC) and uterine carcinosarcoma (UCS) are rare aggressive cancers, characterized by an admixture of adenocarcinoma and areas displaying mesenchymal/sarcomatoid differentiation. We sought to define whether MBCs and UCSs harbor similar patterns of genetic alterations, and whether the different histologic components of MBCs and UCSs are clonally related. Whole‐exome sequencing (WES) data from MBCs (n = 35) and UCSs (n = 57, The Cancer Genome Atlas) were reanalyzed to define somatic genetic alterations, altered signaling pathways, mutational signatures, and genomic features of homologous recombination DNA repair deficiency (HRD). In addition, the carcinomatous and sarcomatous components of an additional cohort of MBCs (n = 11) and UCSs (n = 6) were microdissected separately and subjected to WES, and their clonal relatedness was assessed. MBCs and UCSs harbored recurrent genetic alterations affecting TP53, PIK3CA, and PTEN, similar patterns of gene copy number alterations, and an enrichment in alterations affecting the epithelial‐to‐mesenchymal transition (EMT)‐related Wnt and Notch signaling pathways. Differences were observed, however, including a significantly higher prevalence of FAT3 and FAT1 somatic mutations in MBCs compared to UCSs, and conversely, UCSs significantly more frequently harbored somatic mutations affecting FBXW7 and PPP2R1A as well as HER2 amplification than MBCs. Genomic features of HRD and biallelic alterations affecting bona fide HRD‐related genes were found to be more prevalent in MBCs than in UCSs. The distinct histologic components of MBCs and UCSs were clonally related in all cases, with the sarcoma component likely stemming from a minor subclone of the carcinoma component in the samples with interpretable chronology of clonal evolution. Despite the similar histologic features and pathways affected by genetic alterations, UCSs differ from MBCs on the basis of FBXW7 and PPP2R1A mutations, HER2 amplification, and lack of HRD, supporting the notion that these entities are more than mere phenocopies of the same tumor type in different anatomical sites.

Abbreviations

CCF

cancer cell fraction

CI

clonality index

CNA

copy number alteration

EMT

epithelial‐to‐mesenchymal transition

HRD

homologous recombination DNA repair deficiency

LST

large‐scale state transition

MBC

metaplastic breast carcinoma

NtAI

numerical telomeric allelic imbalance

SNV

single nucleotide variant

TCGA

The Cancer Genome Atlas

TNBC

triple‐negative breast cancer

UCS

uterine carcinosarcoma

WES

whole‐exome sequencing

     

TGFβ promotes YAP‐dependent AXL induction in mesenchymal‐type lung cancer cells

The acquisition of chemoresistance remains a major cause of cancer mortality due to the limited accessibility of targeted or immune therapies. However, given that severe alterations of molecular features during epithelial‐to‐mesenchymal transition (EMT) lead to acquired chemoresistance, emerging studies have focused on identifying targetable drivers associated with acquired chemoresistance. Particularly, AXL, a key receptor tyrosine kinase that confers resistance against targets and chemotherapeutics, is highly expressed in mesenchymal cancer cells. However, the underlying mechanism of AXL induction in mesenchymal cancer cells is poorly understood. Our study revealed that the YAP signature, which was highly enriched in mesenchymal‐type lung cancer, was closely correlated to AXL expression in 181 lung cancer cell lines. Moreover, using isogenic lung cancer cell pairs, we also found that doxorubicin treatment induced YAP nuclear translocation in mesenchymal‐type lung cancer cells to induce AXL expression. Additionally, the concurrent activation of TGFβ signaling coordinated YAP‐dependent AXL expression through SMAD4. These data suggest that crosstalk between YAP and the TGFβ/SMAD axis upon treatment with chemotherapeutics might be a promising target to improve chemosensitivity in mesenchymal‐type lung cancer.

Abbreviations

AUC

area under the curve

AXL

AXL receptor tyrosine kinase

BCL2

B‐cell lymphoma 2

CTD2

cancer target discovery and development

CTGF

connective tissue growth factor

DEG

differentially expressed genes

DOXO

doxorubicin

EMT

epithelial–mesenchymal transition

Eto

etoposide

FDA

Food and Drug Administration

ITGB3

integrin beta‐3

MAPK

mitogen‐activated protein kinase

MMP2

matrix metalloproteinase‐2

MMP9

matrix metalloproteinase‐9

mRNA

messenger RNA

NF‐κB

nuclear factor kappa‐light‐chain‐enhancer of activated B cells

SBE

SMAD binding element

SERPINE1

serpin family E member 1

siRNA

small interfering RNA

ssGSEA

single‐sample gene set enrichment analysis

TCGA

The Cancer Genome Atlas

TGFβ

transforming growth factor beta

YAP

Yes‐associated protein

YAP8SA

mutants of inhibitory phosphorylation site at eight serine to Alanine of YAP

ZEB1

zinc finger E‐box binding homeobox 1

ZEB2

zinc finger E‐box‐binding homeobox 2

     

Clinical implications of plasma circulating tumor DNA in gynecologic cancer patients

Molecular characterization of cancers is important in dictating prognostic factors and directing therapy. Next‐generation sequencing of plasma circulating tumor DNA (ctDNA) offers less invasive, more convenient collection, and a more real‐time representation of a tumor and its molecular heterogeneity than tissue. However, little is known about the clinical implications of ctDNA assessment in gynecologic cancer. We describe the molecular landscape identified on ctDNA, ctDNA concordance with tissue‐based analysis, and factors associated with overall survival (OS) in gynecologic cancer patients with ctDNA analysis. We reviewed clinicopathologic and genomic information for 105 consecutive gynecologic cancer patients with ctDNA analysis, including 78 with tissue‐based sequencing, enrolled in the Profile‐Related Evidence Determining Individualized Cancer Therapy ({"type":"clinical-trial","attrs":{"text":"NCT02478931","term_id":"NCT02478931"}}NCT02478931) trial at the University of California San Diego Moores Cancer Center starting July 2014. Tumors included ovarian (47.6%), uterine (35.2%), cervical (12.4%), vulvovaginal (2.9%), and unknown gynecologic primary (1.9%). Most ovarian and uterine cancers (86%) were high grade. 34% (N = 17) of ovarian cancers had BRCA alterations, and 22% (N = 11) were platinum sensitive. Patients received median 2 (range 0–13) lines of therapy prior to ctDNA collection. Most (75.2%) had at least one characterized alteration on ctDNA analysis, and the majority had unique genomic profiles on ctDNA. Most common alterations were TP53 (N = 59, 56.2% of patients), PIK3CA (N = 26, 24.8%), KRAS (N = 14, 13.3%), BRAF (N = 10, 9.5%), ERBB2 (N = 8, 7.6%), and MYC (N = 8, 7.6%). Higher ctDNA maximum mutation allele frequency was associated with worse OS [hazard ratio (HR): 1.91, P = 0.03], while therapy matched to ctDNA alterations (N = 33 patients) was independently associated with improved OS (HR: 0.34, P = 0.007) compared to unmatched therapy (N = 28 patients) in multivariate analysis. Tissue and ctDNA genomic results showed high concordance unaffected by temporal or spatial factors. This study provides evidence for the utility of ctDNA in determining outcome and individualizing cancer therapy in patients with gynecologic cancer.

Abbreviations

BMI

body mass index

BRCA

breast cancer susceptibility gene

CAP

College of American Pathologists

CI

confidence interval

CLIA

Clinical Laboratory Improvement Amendments

ctDNA

circulating tumor DNA

Del

deletion

HR

hazard ratio

ID

identification number

In/del

insertion/deletion

MAF

mutation allele frequency

NR

not reached

OS

overall survival

PREDICT

Profile‐Related Evidence Determining Individualized Cancer Therapy

SE

standard error

SNV

single nucleotide variant

UCSD

University of California San Diego

VUS

variants of unknown significance

     

Extracellular vesicles and oncogenic signaling

In recent years, extracellular vesicles (EVs) emerged as potential diagnostic and prognostic markers for cancer therapy. While the field of EV research is rapidly developing and their application as vehicles for therapeutic cargo is being tested, little is still known about the exact mechanisms of signaling specificity and cargo transfer by EVs, especially in vivo. Several signaling cascades have been found to use EVs for signaling in the tumor–stroma interaction. These include potentially oncogenic, verbatim transforming, signaling cascades such as Wnt and TGF‐β signaling, and other signaling cascades that have been tightly associated with tumor progression and metastasis, such as PD‐L1 and VEGF signaling. Multiple mechanisms of how these signaling cascades and EVs interplay to mediate these complex processes have been described, such as direct signal activation through pathway components on or in EVs or indirectly by influencing vesicle biogenesis, cargo sorting, or uptake dynamics. In this review, we summarize the current knowledge of EVs, their biogenesis, and our understanding of EV interactions with recipient cells with a focus on selected oncogenic and cancer‐associated signaling pathways. After an in‐depth look at how EVs mediate and influence signaling, we discuss potentially translatable EV functions and existing knowledge gaps.

Abbreviations

EGF(R)

epidermal growth factor (receptor)

EMT

epithelial–mesenchymal transition

EP(s)

extracellular particle(s)

EV(s)

extracellular vesicle(s)

Exo(s)

exosome(s)

Her

human epidermal growth factor receptor

ISEV

International Society for Extracellular Vesicles

MSC

mesenchymal stem cells

MV(s)

microvesicle(s)

MVB

multivesicular body

PD‐L

programmed death‐ligand

TGF‐β

transforming growth factor‐β

VEGF

vascular endothelial growth factor

Wnt

wingless and Int/wingless‐related integration site

     

Targeting immunogenic cell death in cancer

Immunogenic cell death (ICD) is a type of cancer cell death triggered by certain chemotherapeutic drugs, oncolytic viruses, physicochemical therapies, photodynamic therapy, and radiotherapy. It involves the activation of the immune system against cancer in immunocompetent hosts. ICD comprises the release of damage‐associated molecular patterns (DAMPs) from dying tumor cells that result in the activation of tumor‐specific immune responses, thus eliciting long‐term efficacy of anticancer drugs by combining direct cancer cell killing and antitumor immunity. Remarkably, subcutaneous injection of dying tumor cells undergoing ICD has been shown to provoke anticancer vaccine effects in vivo. DAMPs include the cell surface exposure of calreticulin (CRT) and heat‐shock proteins (HSP70 and HSP90), extracellular release of adenosine triphosphate (ATP), high‐mobility group box‐1 (HMGB1), type I IFNs and members of the IL‐1 cytokine family. In this review, we discuss the cell death modalities connected to ICD, the DAMPs exposed during ICD, and the mechanism by which they activate the immune system. Finally, we discuss the therapeutic potential and challenges of harnessing ICD in cancer immunotherapy.

Abbreviations

ATP

adenosine triphosphate

BAK

BCL‐2 homologous antagonist killer

BAX

BCL‐2‐associated X protein

BCL‐2

B‐cell lymphoma 2

BID

BH3‐interacting domain death agonist

c‐FLIP

cellular FLICE‐like inhibitory protein

cGAMP

cyclic guanosine monophosphate–adenosine monophosphate

cGAS

cyclic GMP‐AMP synthase

CRT

calreticulin

CXCL10

chemokine C‐X‐C motif ligand 10

DAMPs

damage‐associated molecular patterns

DCs

dendritic cells

DISC

death‐inducing signaling complex

ER

endoplasmic reticulum

FADD

FAS‐associated protein with death domain

FASL

FAS ligand

GSDMD

gasdermin D

GSDMD^NT

N‐terminal fragment of gasdermin D

GSDME

gasdermin E

HMGB1

high‐mobility group box‐1

HSP

heat‐shock proteins

Hyp‐PDT

hypericin‐based photodynamic therapy

ICD

immunogenic cell death

IFN

interferon

IFNAR

IFN‐α and IFN‐β receptors

IL

interleukin

IRF3

interferon regulatory factor 3

ISGs

IFN‐stimulated genes

LPS

lipopolysaccharide

MAPK

mitogen‐activated protein kinase

MHC

major histocompatibility complex

MLKL

mixed‐lineage kinase‐like

MOMP

mitochondrial outer membrane permeabilization

mtDNA

mitochondrial DNA

NF‐κB

nuclear factor kappa‐light‐chain‐enhancer of activated B cells

NK cells

natural killer cells

NLR

NOD‐like receptor

NLRP3

NOD‐like receptor family, pyrin domain‐containing 3 protein

P2RX7

purinergic receptor P2X 7

PD‐L1

programmed death ligand

PRRs

pattern recognition receptors

PS

phosphatidyl serine

RCD

regulated cell death

RIPK1

receptor‐interacting serine/threonine protein kinase 1

RIPK3

receptor‐interacting serine/threonine protein kinase 3

ROS

reactive oxygen species

STING

stimulator of interferon genes

tBID

truncated form of BID

TBK1

TANK‐binding kinase 1

TLR

Toll‐like receptor

TNF

tumor necrosis factor

TRAIL

TNF‐related apoptosis‐inducing ligand

ZBP

Z‐DNA‐binding protein

     

Defining the dimensions of circulating tumor cells in a large series of breast,prostate, colon,and bladder cancer patients

Circulating tumor cells (CTCs) in the blood of cancer patients are of high clinical relevance. Since detection and isolation of CTCs often rely on cell dimensions, knowledge of their size is key. We analyzed the median CTC size in a large cohort of breast (BC), prostate (PC), colorectal (CRC), and bladder (BLC) cancer patients. Images of patient‐derived CTCs acquired on cartridges of the FDA‐cleared CellSearch^® method were retrospectively collected and automatically re‐analyzed using the accept software package. The median CTC diameter (μm) was computed per tumor type. The size differences between the different tumor types and references (tumor cell lines and leukocytes) were nonparametrically tested. A total of 1962 CellSearch^® cartridges containing 71 612 CTCs were included. In BC, the median computed diameter (CD) of patient‐derived CTCs was 12.4 μm vs 18.4 μm for cultured cell line cells. For PC, CDs were 10.3 μm for CTCs vs 20.7 μm for cultured cell line cells. CDs for CTCs of CRC and BLC were 7.5 μm and 8.6 μm, respectively. Finally, leukocytes were 9.4 μm. CTC size differed statistically significantly between the four tumor types and between CTCs and the reference data. CTC size differences between tumor types are striking and CTCs are smaller than cell line tumor cells, whose size is often used as reference when developing CTC analysis methods. Based on our data, we suggest that the size of CTCs matters and should be kept in mind when designing and optimizing size‐based isolation methods.

Abbreviations

ACCEPT

Automated CTC Classification, Enumeration, and PhenoTyping software

BC

breast cancer

BLC

bladder cancer

CD

computed diameter

CEL

cultured tumor cell (cell line)

CK

cytokeratin

CRC

colorectal cancer

CTC‐L

circulating tumor cells derived from cerebrospinal fluid (liquor)

CTCs

circulating tumor cells

DAPI

4′6‐diamidino‐2‐phenylindole

EMT

epithelial–mesenchymal transition

EpCAM

epithelial cell adhesion molecule

IQR

interquartile range

KW test

Kruskal–Wallis test

MWU test

Mann–Whitney U test

NCR

nucleus/cytoplasm ratio

P2A

perimeter to area

PC

prostate cancer

TIF

tagged Image Format files

TXT

text file

μm

micrometer

µm²

square micrometers

     

Clinical significance of signal regulatory protein alpha (SIRPα) expression in esophageal squamous cell carcinoma

Signal regulatory protein alpha (SIRPα) is a type I transmembrane protein that inhibits macrophage phagocytosis of tumor cells upon interaction with CD47, and the CD47‐SIRPα pathway acts as an immune checkpoint factor in cancers. This study aims to clarify the clinical significance of SIRPα expression in esophageal squamous cell carcinoma (ESCC). First, we assessed SIRPα expression using RNA sequencing data of 95 ESCC tissues from The Cancer Genome Atlas (TCGA) and immunohistochemical analytic data from our cohort of 131 patients with ESCC. Next, we investigated the correlation of SIRPα expression with clinicopathological factors, patient survival, infiltration of tumor immune cells, and expression of programmed cell death‐ligand 1 (PD‐L1). Overall survival was significantly poorer with high SIRPα expression than with low expression in both TCGA and our patient cohort (P < .001 and P = .027, respectively). High SIRPα expression was associated with greater depth of tumor invasion (P = .0017). Expression of SIRPα was also significantly correlated with the tumor infiltration of M1 macrophages, M2 macrophages, CD8⁺ T cells, and PD‐L1 expression (P < .001, P < .001, P = .03, and P < .001, respectively). Moreover, patients with SIRPα/PD‐L1 coexpression tended to have a worse prognosis than patients with expression of either protein alone or neither. Taken together, SIRPα indicates poor prognosis in ESCC, possibly through inhibiting macrophage phagocytosis of tumor cells and inducing suppression of antitumor immunity. Signal regulatory protein alpha should be considered as a potential therapeutic target in ESCC, especially if combined with PD‐1‐PD‐L1 blockade.