The "watch-and-wait" approach is a common treatment option amongst patients with locally advanced rectal cancer (LARC). However, the diagnostic sensitivity of clinical modalities, such as colonoscopy ...and magnetic resonance imaging to determine pathological response, is not high. We analysed the clinical utility of circulating tumour DNA (ctDNA) of patients with LARC to predict response to preoperative therapy and postoperative recurrence.
A serial ctDNA analysis of 222 plasma samples from 85 patients with LARC was performed using amplicon-based deep sequencing on a cell-free DNA panel covering 14 genes with over 240 hotspots.
ctDNA was detected in 57.6% and 22.3% of samples at baseline and after preoperative treatment, respectively, which was significantly different (P = 0.0003). Change in ctDNA was an independent predictor of complete response to preoperative therapy (P = 0.0276). In addition, postoperative ctDNA and carcinoembryonic antigen (CEA) were independent prognostic markers for risk of recurrence after surgery (ctDNA, P = 0.0127 and CEA, P = 0.0105), with a combined analysis having cumulative effects on recurrence-free survival (P = 1.0 × 10
).
Serial ctDNA analysis may offer clinically useful predictive and prognostic markers for response to preoperative therapy and postoperative recurrence in patients with LARC.
Epithelial‐mesenchymal transition (EMT) is a reversible and dynamic process hypothesized to be co‐opted by carcinoma during invasion and metastasis. Yet, there is still no quantitative measure to ...assess the interplay between EMT and cancer progression. Here, we derived a method for universal EMT scoring from cancer‐specific transcriptomic EMT signatures of ovarian, breast, bladder, lung, colorectal and gastric cancers. We show that EMT scoring exhibits good correlation with previously published, cancer‐specific EMT signatures. This universal and quantitative EMT scoring was used to establish an EMT spectrum across various cancers, with good correlation noted between cell lines and tumours. We show correlations between EMT and poorer disease‐free survival in ovarian and colorectal, but not breast, carcinomas, despite previous notions. Importantly, we found distinct responses between epithelial‐ and mesenchymal‐like ovarian cancers to therapeutic regimes administered with or without paclitaxel in vivo and demonstrated that mesenchymal‐like tumours do not always show resistance to chemotherapy. EMT scoring is thus a promising, versatile tool for the objective and systematic investigation of EMT roles and dynamics in cancer progression, treatment response and survival.
Synopsis
A novel EMT scoring method reveals that EMT status does not unanimously correlate with poorer overall and disease‐free survival. Different EMTed tumours show distinct responses to certain chemotherapeutics, with the potential to stratify patients by EMT status.
A novel scoring method was developed based on transcriptomics to universally estimate and compare the Epithelial‐Mesenchymal Transition (EMT) phenotype across cancer types.
A spectrum of EMT was established across more than 15 cancers using this EMT scoring method.
Correlations of EMT status with poorer overall‐ and disease‐free survival were not unanimously observed in all cancers.
Differential and preferential responses of EMTed tumours to certain chemotherapeutics were observed, suggesting the potential to stratify patients by EMT status.
A novel EMT scoring method reveals that EMT status does not unanimously correlate with poorer overall and disease‐free survival. Different EMTed tumours show distinct responses to certain chemotherapeutics, with the potential to stratify patients by EMT status.
Gastric cancer in young adults has been pointed out to comprise a subgroup associated with distinctive clinicopathological features, including an equal gender distribution, advanced disease, and ...diffuse‐type histology. Comprehensive molecular analyses of gastric cancers have led to molecular‐based classifications and to specific and effective treatment options. The molecular traits of gastric cancers in young adults await investigations, which should provide a clue to explore therapeutic strategies. Here, we studied 146 gastric cancer patients diagnosed at the age of 40 years or younger at the Cancer Institute Hospital (Tokyo, Japan). Tumor specimens were examined for Helicobacter pylori infection, Epstein‐Barr virus positivity, and for the expression of mismatch repair genes to indicate microsatellite instability. Overexpression, gene amplifications, and rearrangements of 18 candidate driver genes were examined by immunohistochemistry and FISH. Although only a small number of cases were positive for Epstein‐Barr virus and microsatellite instability (n = 2 each), we repeatedly found tumors with gene fusion between a tight‐junction protein claudin, CLDN18, and a regulator of small G proteins, ARHGAP, in as many as 22 cases (15.1%), and RNA sequencing identified 2 novel types of the fusion. Notably, patients with the CLDN18‐ARHGAP fusion revealed associations between aggressive disease and poor prognosis, even when grouped by their clinical stage. These observations indicate that a fusion gene between CLDN18 and ARHGAP is enriched in younger age‐onset gastric cancers, and its presence could contribute to their aggressive characteristics.
In our gastric cancer in young adult cohort, we found enrichment of fusion genes between CLDN18 and ARHGAP. The positivity of the CLDN18‐ARHGAP fusion relates to advanced disease and poor prognosis, indicating its clinical relevance.
Background- Inflammation plays a key role in the pathophysiology of myocardial ischemia/reperfusion (I/R) injury; however, the mechanism by which myocardial I/R induces inflammation remains unclear. ...Recent evidence indicates that a sterile inflammatory response triggered by tissue damage is mediated through a multiple-protein complex called the inflammasome. Therefore, we hypothesized that the inflammasome is an initial sensor for danger signal(s) in myocardial I/R injury. Methods and Results- We demonstrate that inflammasome activation in cardiac fibroblasts, but not in cardiomyocytes, is crucially involved in the initial inflammatory response after myocardial I/R injury. We found that inflammasomes are formed by I/R and that its subsequent activation of inflammasomes leads to interleukin-1β production, resulting in inflammatory responses such as inflammatory cell infiltration and cytokine expression in the heart. In mice deficient for apoptosis-associated speck-like adaptor protein and caspase-1, these inflammatory responses and subsequent injuries, including infarct development and myocardial fibrosis and dysfunction, were markedly diminished. Bone marrow transplantation experiments with apoptosis-associated speck-like adaptor protein-deficient mice revealed that inflammasome activation in bone marrow cells and myocardial resident cells such as cardiomyocytes or cardiac fibroblasts plays an important role in myocardial I/R injury. In vitro experiments revealed that hypoxia/reoxygenation stimulated inflammasome activation in cardiac fibroblasts, but not in cardiomyocytes, and that hypoxia/reoxygenation-induced activation was mediated through reactive oxygen species production and potassium efflux. Conclusions- Our results demonstrate the molecular basis for the initial inflammatory response after I/R and suggest that the inflammasome is a potential novel therapeutic target for preventing myocardial I/R injury.
Carcinosarcoma (CS) of the uterus or ovary is a rare, aggressive and biphasic neoplasm composed of carcinoma and sarcoma elements. Previous genomic studies have identified the driver genes and ...genomic properties associated with CS. However, there is still no molecular subtyping scheme with clinical relevance for this disease. Here, we sequence 109 CS samples, focusing on 596 genes. We identify four molecular subtypes that resemble those observed in endometrial carcinoma: POLE-mutated, microsatellite instability, copy number high, and copy number low subtypes. These molecular subtypes are linked with DNA repair deficiencies, potential therapeutic strategies, and multiple clinicopathological features, including patient outcomes. Multi-regional comparative sequencing reveals genomic alteration-independent CS cell differentiation. Transcriptome and DNA methylome analyses confirm epithelial-mesenchymal transition as a mechanism of sarcoma differentiation. The current study thus provides therapeutic possibilities for CS as well as clues to understanding the molecular histogenic mechanism of its development.
Abdominal aortic aneurysm (AAA) is considered a chronic inflammatory disease; however, the molecular basis underlying the sterile inflammatory response involved in the process of AAA remains unclear. ...We previously showed that the inflammasome, which regulates the caspase-1-dependent interleukin-1β production, mediates the sterile cardiovascular inflammatory responses. Therefore, we hypothesized that the inflammasome is a key mediator of initial inflammation in AAA formation.
Apoptosis-associated speck-like protein containing a caspase recruitment domain is highly expressed in adventitial macrophages in human and murine AAA tissues. Using an established mouse model of AAA induced by continuous infusion of angiotensin II in Apoe(-/-) mice, NLR family pyrin domain containing 3 (NLRP3), apoptosis-associated speck-like protein containing a caspase recruitment domain, and caspase-1 deficiency in Apoe(-/-) mice were shown to decrease the incidence, maximal diameter, and severity of AAA along with adventitial fibrosis and inflammatory responses significantly, such as inflammatory cell infiltration and cytokine expression in the vessel wall. NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain, and caspase-1 deficiency in Apoe(-/-) mice also reduced elastic lamina degradation and metalloproteinase activation in the early phase of AAA formation. Furthermore, angiotensin II stimulated generation of mitochondria-derived reactive oxygen species in the adventitial macrophages, and this mitochondria-derived reactive oxygen species generation was inhibited by NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain, and caspase-1 deficiency. In vitro experiments revealed that angiotensin II stimulated the NLRP3 inflammasome activation and subsequent interleukin-1β release in macrophages, and this activation was mediated through an angiotensin type I receptor/mitochondria-derived reactive oxygen species-dependent pathway.
Our results demonstrate the importance of the NLRP3 inflammasome in the initial inflammatory responses in AAA formation, indicating its potential as a novel therapeutic target for preventing AAA progression.
Colorectal cancer (CRC) is a heterogenous disease, and patients have differences in therapeutic response. However, the mechanisms underlying interpatient heterogeneity in the response to ...chemotherapeutic agents remain to be elucidated, and molecular tumor characteristics are required to select patients for specific therapies. Patient‐derived organoids (PDOs) established from CRCs recapitulate various biological characteristics of tumor tissues, including cellular heterogeneity and the response to chemotherapy. Patient‐derived organoids established from CRCs show various morphologies, but there are no criteria for defining these morphologies, which hampers the analysis of their biological significance. Here, we developed an artificial intelligence (AI)‐based classifier to categorize PDOs based on microscopic images according to their similarity in appearance and classified tubular adenocarcinoma‐derived PDOs into six types. Transcriptome analysis identified differential expression of genes related to cell adhesion in some of the morphological types. Genes involved in ribosome biogenesis were also differentially expressed and were most highly expressed in morphological types showing CRC stem cell properties. We identified an RNA polymerase I inhibitor, CX‐5641, to be an upstream regulator of these type‐specific gene sets. Notably, PDO types with increased expression of genes involved in ribosome biogenesis were resistant to CX‐5461 treatment. Taken together, these results uncover the biological significance of the morphology of PDOs and provide novel indicators by which to categorize CRCs. Therefore, the AI‐based classifier is a useful tool to support PDO‐based cancer research.
We developed an artificial intelligence (AI)‐based classifier to categorize Patient‐derived organods(PDOs). Transcriptome analysis identified differential expression of genes related to cell adhesion and ribosome biogenesis and an RNA polymerase I inhibitor, CX‐5641, exhibeted type‐specific response. These results uncover the biological significance of the morphology of PDOs and the AI‐based classifier is a useful tool to support PDO‐based cancer research.
We present the results of matrix-assisted laser desorption/ionization (MALDI) imaging and direct molecular identification using tandem mass spectrometry (MS/MS) in colon cancer liver metastasis. ...Cancer tissue was removed from a Japanese patient and frozen immediately without any fixations. The sections were sliced to a thickness of 3
μm. The matrix for lipid ionization was 2,6-dihydroxy acetophenone. The matrix solution was applied with an airbrush into a thin uniform matrix layer on the tissue surface. After two-dimensional laser scanning, the images were reconstructed as a function of
m/
z from a few hundred obtained spectra. In the obtained images, the existence of molecules was represented by a pseudo-color corresponding to the signal intensity. In a feasibility study, we picked up a localized signal,
m/
z 725 in a cancerous area. The MS/MS result suggested that
m/
z 725 was sphingomyelin(16:0)+Na. Thus, we successfully show the feasibility of MALDI imaging as a tool for the analysis of pathological specimens.
Aging is considered to be accelerated by insulin signaling in lower organisms, but it remained unclear whether this could hold true for mammals. Here we show that mice with skeletal muscle-specific ...double knockout of Akt1/2, key downstream molecules of insulin signaling, serve as a model of premature sarcopenia with insulin resistance. The knockout mice exhibit a progressive reduction in skeletal muscle mass, impairment of motor function and systemic insulin sensitivity. They also show osteopenia, and reduced lifespan largely due to death from debilitation on normal chow and death from tumor on high-fat diet. These phenotypes are almost reversed by additional knocking out of Foxo1/4, but only partially by additional knocking out of Tsc2 to activate the mTOR pathway. Overall, our data suggest that, unlike in lower organisms, suppression of Akt activity in skeletal muscle of mammals associated with insulin resistance and aging could accelerate osteosarcopenia and consequently reduce lifespan.
During brain development, neural precursor cells (NPCs) expand initially, and then switch to generating stage-specific neurons while maintaining self-renewal ability. Because the NPC pool at the ...onset of neurogenesis crucially affects the final number of each type of neuron, tight regulation is necessary for the transitional timing from the expansion to the neurogenic phase in these cells. However, the molecular mechanisms underlying this transition are poorly understood. Here, we report that the telencephalon-specific loss of PAR3 before the start of neurogenesis leads to increased NPC proliferation at the expense of neurogenesis, resulting in disorganized tissue architecture. These NPCs demonstrate hyperactivation of hedgehog signaling in a smoothened-dependent manner, as well as defects in primary cilia. Furthermore, loss of PAR3 enhanced ligand-independent ciliary accumulation of smoothened and an inhibitor of smoothened ameliorated the hyperproliferation of NPCs in the telencephalon. Thus, these findings support the idea that PAR3 has a crucial role in the transition of NPCs from the expansion phase to the neurogenic phase by restricting hedgehog signaling through the establishment of ciliary integrity.
PDF
