Identification of BRAF Inhibitor Resistance-associated lncRNAs Using Genome-scale CRISPR-Cas9 Transcriptional Activation Screening.

BACKGROUND/AIM: Approximately 50% of melanomas harbor the BRAF V600E mutation and targeted therapies using BRAF inhibitors improve patient outcomes. Nonetheless, resistance to BRAF inhibitors develops rapidly and remains a challenge in melanoma treatment. In this study, we attempted to isolate long noncoding RNAs (lncRNAs) involved in BRAF inhibitor resistance using a comprehensive screening method. MATERIALS AND METHODS: We used a CRISPR-Cas9 synergistic activation mediator (SAM) protein complex in a genome-scale transcriptional activation assay to screen for candidate lncRNA genes related to BRAF inhibitor resistance. Correlation analysis was performed between expression levels of isolated lncRNA genes and IC50 of dabrafenib in a BRAF-mutated melanoma cell line. Next, online databases were used to construct the lncRNA-miRNA-mRNA regulatory network. Finally, we evaluated the significance of the expression levels of these lncRNAs and mRNAs as biomarkers using clinical specimens. RESULTS: We isolated three BRAF inhibitor resistance-associated lncRNA genes, namely SNHG16, NDUFV2-AS1, and LINC01502. We constructed a lncRNA-miRNA-mRNA network of 13 nodes consisting of three lncRNAs, six miRNAs, and four mRNAs. The lncRNAs and target mRNAs from each regulatory axis significantly and positively correlated with each other. Finally, Kaplan-Meier analysis showed that higher expression levels of MITF, which was up-regulated by LINC01502, were significantly associated with worse prognosis in BRAF V600E-mutated melanoma. CONCLUSION: The identification of these BRAF inhibitor resistance-associated lncRNA genes at the genomic scale and the establishment of the lncRNA-miRNA-mRNA regulatory network provides new insights into the underlying mechanisms of BRAF inhibitor resistance in melanoma.

Severity of SARS-CoV-2 infection in pregnant women and their neonates during the Omicron period compared to the pre-Omicron period: A retrospective cohort study.

AIM: To compare the clinical outcomes among women diagnosed with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection during pregnancy, and their neonates, during the period when the Omicron variant predominated in Japan with those of the pre-Omicron variant period. METHODS: We conducted a retrospective single-center cohort study between August 1, 2020, and June 30, 2022. The cohort was divided into pre-Omicron group (August 1, 2020 to November 30, 2021) and Omicron group (December 1, 2021 to June 30, 2022). The primary outcome was maternal intensive care unit (ICU) admission during the perinatal period. The secondary outcomes were maternal oxygen administration before and after delivery, preterm birth (PTB), and low birth weight (LBW). RESULTS: During the study period, 81 pregnant women were admitted to the hospital with SARS-CoV-2 infection (pre-Omicron period, n = 28; Omicron period, n = 53). SARS-CoV-2 infection during the Omicron period was associated with lower risk of maternal ICU admission (adjusted-odds ratio [aOR]: 0.10, 95% confidence interval [CI]: 0.01-1.23, p = 0.072), oxygen administration via a nasal cannula or mask (aOR: 0.18, 95% CI: 0.03-0.96, p = 0.045), PTB (aOR: 0.15, 95% CI: 0.04-0.51, p = 0.002), and LBW (aOR: 0.13, 95% CI: 0.03-0.55, p = 0.005). CONCLUSION: Among pregnant women, SARS-CoV-2 infection during the Omicron period was associated with reduced risk of maternal ICU admission, requiring supplemental oxygen, PTB, and LBW. This can be attributable to lower virulence of the Omicron variant and higher vaccination coverage during the Omicron period.

The MDM2 and CDKN2A Copy-number-variation Influence the TP53-signature-score in Wild-type TP53 Luminal Type Breast Cancer.

BACKGROUND/AIM: The TP53-signature is a multi-gene signature that can predict TP53 structural mutations. It has presented remarkable ability to predict the prognosis of early-stage breast cancer. However, some samples presented discordance with the signature status and structure status. We aimed to investigate whether the mRNA expression levels or copy number variation (CNV) of MDM2 and CDKN2A influence the TP53-signature-score, subtype classification, and prognosis prediction in TP53 wild-type, luminal type early-stage breast cancer samples. MATERIALS AND METHODS: We selected TP53 wild-type, luminal type early-stage breast cancer samples from The Cancer Genome Atlas (TCGA) and Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) cohorts. Then, we analyzed the correlation between the TP53-signature-score and mRNA expression levels or CNV of MDM2 and CDKN2A. RESULTS: The samples with MDM2 copy number (CN) amplification or those with CDKN2A CN deep deletion presented higher TP53-signature-score. Moreover, samples with MDM2 CN amplification or those with CDKN2A CN deep deletion had more characteristics of the luminal B type. In addition, they showed lower estrogen response early score, which correlated with response to endocrine therapy in breast cancer. However, MDM2 and CDKN2A mRNA expression did not present the same tendency. Furthermore, samples with MDM2 CN amplification or those with CDKN2A CN deep deletion had a worse prognosis in METABRIC cohort. CONCLUSION: The MDM2 or CDKN2A CNV may be useful for classifying subtypes and predicting prognosis more accurately in TP53 wild-type, luminal type early-stage breast cancer patients.

Possible reversibility between epithelioid and sarcomatoid types of mesothelioma is independent of ERC/mesothelin expression.

BACKGROUND: Mesothelioma is histologically divided into three subgroups: epithelioid, sarcomatoid, and biphasic types. The epithelioid or sarcomatoid type is morphologically defined by polygonal or spindle-like forms of cells, respectively. The biphasic type consists of both components. It is not yet understood how histological differentiation of mesothelioma is regulated. ERC/mesothelin is expressed in most cases of the epithelioid type, but not in the sarcomatoid type of mesothelioma. Consequently, its expression is well correlated to the histological subtype. We hypothesized that ERC/mesothelin expression influences the histological differentiation of mesothelioma, and tested this hypothesis. METHODS: We performed studies using the overexpression or knockdown of ERC/mesothelin in mesothelioma cells to examine its effect on cellular morphology, growth kinetics, or migration/invasion activity, in vitro. We then transplanted ERC/mesothelin-overexpressing and control cells into the intraperitoneal space of mice. We examined the effect of ERC/mesothelin overexpression on mouse survival and tumor phenotype. RESULTS: In vitro cell culture manipulations of ERC/mesothelin expression did not affect cellular morphology or proliferation, although its overexpression enhanced cellular adhesion and the migration/invasion activity of mesothelioma cells. The survival rate of mice following intraperitoneal transplantation of ERC/mesothelin-overexpressing mesothelioma cells was significantly lower than that of mice with control cells. The histological evaluation of the tumors, however, did not show any morphological difference between two groups, and our hypothesis was not validated. Unexpectedly, both groups (ERC/mesothelin-overexpressing and control) of mesothelioma cells that were morphologically monophasic and spindle-like in vitro differentiated into a biphasic type consisting of polygonal and spindle-like components in the transplanted tumor, irrespective of ERC/mesothelin expression. CONCLUSIONS: These results suggested that the histological transition of mesothelioma between epithelioid and sarcomatoid types may be reversible and regulated not by ERC/mesothelin, but by other unknown mechanisms.

A novel diagnostic system to evaluate epidermal growth factor receptor impact as a prognostic and therapeutic indicator for lung adenocarcinoma.

Many driver pathways for cancer cell proliferation have been reported. Driver pathway activation is often evaluated based on a single hotspot mutation such as EGFR L858R. However, because of complex intratumoral networks, the impact of a driver pathway cannot be predicted based on only a single gene mutation. Here, we developed a novel diagnostic system named the "EGFR impact score" which is based on multiplex mRNA expression profiles, which can predict the impact of the EGFR pathway in lung cancer cells and the effect of EGFR-tyrosine kinase inhibitors on malignancy. The EGFR impact score indicated robust predictive power for the prognosis of early-stage lung cancer because this score can evaluate the impact of the EGFR pathway on the tumor and genomic instability. Additionally, the molecular features of the poor prognostic group resembled those of biomarkers associated with immune checkpoint inhibitors. The EGFR impact score is a novel prognostic and therapeutic indicator for lung adenocarcinoma.

Two-stage goal-directed therapy protocol for non-donor open hepatectomy: an interventional before-after study.

PURPOSE: Hemodynamic management during low central venous pressure (L-CVP)-assisted hepatectomy involves fluid restriction during resection and fluid resuscitation after resection. Recently, high stroke volume variation (SVV) has been reported as an alternative to L-CVP for reducing blood loss during a hepatectomy. The current study evaluated the impact of a newly implemented SVV-based goal-directed therapy (GDT) protocol on blood loss during hepatectomy. METHODS: We conducted a before-after comparative study, which included L-CVP-assisted hepatectomy cases (control group) and GDT-assisted hepatectomy cases (intervention group). The GDT protocol included SVV, cardiac index, and mean arterial pressure as hemodynamic parameters. The target SVV ranges were ≥ 13% and ≤ 12% before and after the resection, respectively. The primary endpoint was the proportion of patients whose blood loss was < 400 mL (median of our hepatectomy cases) in the GDT group, and it was compared to a predefined threshold of 50%. We also investigated factors associated with blood loss using multiple regression analysis. RESULTS: We included 66 patients in the control group and 50 in the GDT group. In the GDT group, the median blood loss was 220 mL and 36 patients (72%) lost < 400 mL blood. This was significantly greater than 50% (P < 0.001). Post-resection GDT-guided fluid optimization reduced positive intraoperative fluid balance compared to that achieved by the conventional fluid therapy used in the control. Multiple regression analysis showed that GDT application, epidural anesthesia, operative time, and hydroxyethyl-starch infusion volume were associated with blood loss. CONCLUSION: Compared to conventional management, SVV-guided GDT may reduce blood loss during hepatectomies.

Anesthetic management for cesarean section in a patient receiving transplacental treatment of fetal tachyarrhythmia: a case report.

BACKGROUND: Although rare, long-lasting fetal tachyarrhythmia often leads to fetal heart failure and hydrops. Some mothers receive transplacental treatment of fetal tachyarrhythmia (TTFT), which can potentially worsen maternal hypotension and bradycardia. Moreover, the use of rescue cardiovascular agents intraoperatively can worsen fetal tachycardia. However, reports of the anesthetic management of patients receiving TTFT are rare. CASE PRESENTATION: A 31-year-old woman who was receiving digoxin and sotalol for TTFT underwent planned elective cesarean section. The fetus had hypoplastic left heart syndrome, hydrops, and tachycardia. We used combined spinal-epidural anesthesia with a reduced dose of local anesthetic. We also employed a non-invasive continuous hemodynamic monitoring system. The mother's systolic blood pressure remained at ≥ 90% of the baseline value; intraoperative administration of rescue cardiovascular agents was not required. CONCLUSIONS: We successfully anesthetized a woman for cesarean section, who was receiving TTFT for fetal tachyarrhythmia, using combined spinal-epidural anesthesia and non-invasive continuous hemodynamic monitoring.

Identification and characterization of a novel adenomatous polyposis coli mutation in adult pancreatoblastoma.

During next generation sequencing (NGS) analysis, many missense mutations were found in a well-known oncogene, many of which were variant of uncertain significance mutations. We recently treated an adult patient with pancreatoblastoma by chemotherapy. Using an NGS cancer panel, we found a previously unreported missense mutation in the 1835 codon of the adenomatous polyposis coli (APC) gene. We also found a heterogeneous mutation in the 1835 codon of the APC gene in the patient's germline by Sanger sequencing. Although this patient did not have a history of familial adenomatous polyposis, functional analysis suggested the R1835G mutant APC showed attenuated repression of Wnt/ß-catenin signaling activity. This is the first report showing a novel APC missense mutation involved in the onset of adult pancreatoblastoma.

Smyd5 plays pivotal roles in both primitive and definitive hematopoiesis during zebrafish embryogenesis.

Methylation of histone tails plays a pivotal role in the regulation of a wide range of biological processes. SET and MYND domain-containing protein (SMYD) is a methyltransferase, five family members of which have been identified in humans. SMYD1, SMYD2, SMYD3, and SMYD4 have been found to play critical roles in carcinogenesis and/or the development of heart and skeletal muscle. However, the physiological functions of SMYD5 remain unknown. To investigate the function of Smyd5 in vivo, zebrafish were utilised as a model system. We first examined smyd5 expression patterns in developing zebrafish embryos. Smyd5 transcripts were abundantly expressed at early developmental stages and then gradually decreased. Smyd5 was expressed in all adult tissues examined. Loss-of-function analysis of Smyd5 was then performed in zebrafish embryos using smyd5 morpholino oligonucleotide (MO). Embryos injected with smyd5-MO showed normal gross morphological development, including of heart and skeletal muscle. However, increased expression of both primitive and definitive hematopoietic markers, including pu.1, mpx, l-plastin, and cmyb, were observed. These phenotypes of smyd5-MO zebrafish embryos were also observed when we introduced mutations in smyd5 gene with the CRISPR/Cas9 system. As the expression of myeloid markers was elevated in smyd5 loss-of-function zebrafish, we propose that Smyd5 plays critical roles in hematopoiesis.

A novel mouse model of intrahepatic cholangiocarcinoma induced by liver-specific Kras activation and Pten deletion.

Intrahepatic cholangiocarcinoma (ICC) is an aggressive malignancy with poor prognosis and its incidence is increasing worldwide. Recently, several types of cells have been considered as the origin of ICC, namely cholangiocytes, liver progenitor cells, and hepatocytes. Here, we have established a novel mouse model of ICC by liver-specific Kras activation and Pten deletion. An activating mutation of Kras in combination with deletion of Pten was introduced in embryonic hepatic bipotential progenitor cells (so-called hepatoblasts) and mature hepatocytes using the Cre-loxP system. As a result, liver-specific Kras activation and homozygous Pten deletion cooperated to induce ICCs exclusively. In contrast, Kras activation in combination with heterozygous Pten deletion induced both ICCs and HCCs, whereas Kras activation alone resulted in HCCs but not ICCs. Furthermore, a cell-lineage visualization system using tamoxifen-inducible Cre-loxP demonstrated that the ICCs did not originate from hepatocytes but from cholangiocytes. Our data suggest that mice carrying liver-specific Kras activation in combination with homozygous Pten deletion should be useful for the investigation of therapeutic strategies for human ICC.

[Comparison of the Effect of Periarticular Infiltration Analgesia versus Sciatic Nerve Block for Total Knee Arthroplasty].

BACKGROUND: Sciatic nerve block (SNB) is widely used as a supplemental analgesia after total knee arthroplasty (TKA) combined with femoral nerve block (FNB). Despite its effectiveness, SNB often causes peroneal nerve paralysis, which makes it difficult to detect peroneal nerve injury by surgical process. Recently, periarticular infiltration analgesia (PIA) is reported that it provides analgesia without peroneal nerve paralysis. We conducted a retrospective analysis to compare the effectiveness of SNB and PIA. METHODS: This study was approved by the local institutional ethics committee; 17 patients undergoing TKA under general anesthesia with continuous femoral nerve block were enrolled in the study. All patients received continuous FNB. Nine patients received sciatic nerve block successively, while 8 patients received PIA around the time of insertion of artificial joint. Primary outcome measure was the frequency of peroneal nerve paralysis when the patients woke up. Secondary outcome measures included numerical rating scale (NRS) until postoperative day 3. RESULTS: While there were 6 patients who had peroneal nerve paralysis in the SNB group, none of them had it in the PIA group (P = 0.009). There were no significant differences of the NRSs between the two groups. CONCLUSIONS: PIA provided sufficient analgesia after TKA without peroneal nerve paralysis.

Impact of chromosome 17q deletion in the primary lesion of colorectal cancer on liver metastasis.

Colorectal cancer is a prevalent malignancy worldwide, and investigations are required to elucidate the underlying carcinogenic mechanisms. Amongst these mechanisms, de novo carcinogenesis and the adenoma to carcinoma sequence, are the most understood. Metastasis of colorectal cancer to the liver often results in fatality, therefore, it is important for any associated risk factors to be identified. Regarding the treatment of the disease, it is important to manage not only the primary colorectal tumor, but also the liver metastases. Previously, through gene variation analysis, chromosomal loss has been indicated to serve an important role in liver metastasis. Such analysis may aid in the prediction of liver metastasis risk, alongside individual responses to treatment, thus improving the management of colorectal cancer. In the present study, we aimed to clarify a cause of the liver metastasis of colorectal cancer using comparative genomic hybridization analysis. A total of 116 frozen samples were analyzed from patients with advanced colorectal cancer that underwent surgery from 2004 to 2011. The present study analyzed mutations within tumor suppressor genes non-metastatic gene 23 (NM23), deleted in colorectal carcinoma (DCC) and deleted in pancreatic carcinoma, locus 4 (DPC4), which are located on chromosomes 17 and 18 and have all been reported to affect liver metastasis of colorectal cancer. The association between chromosomal abnormalities (duplication and deletion) and liver metastasis of colorectal cancer was evaluated using comparative genomic hybridization. Cluster analysis indicated that the group of patients lacking the long arm of chromosome 17 demonstrated the highest rate of liver metastasis. No significant association was observed between the frequency of liver metastases for synchronous and heterochronous colorectal cancer cases and gene variation (P=0.206). However, when these liver metastasis cases were divided into the synchronous and heterochronous types, the ratio of each was significantly different between gene variation groups, classified by the existence of the 17q deletion (P=0.023). These results indicate that the deletion of 17q may act as a predictive marker of liver metastasis in postoperative states.

Critical roles of DNase1l3l in lens nuclear degeneration in zebrafish.

The vertebrate lens undergoes organelle and nuclear degradation during lens development, allowing the lens to become transparent. DNase2b is an enzyme responsible for nuclear degradation in the mouse lens; however, dnase2b expression in zebrafish showed a distribution pattern that differed from that in mice. No zebrafish dnase2b was detected by reverse-transcription polymerase chain reaction until around 120 h postfertilization (hpf), suggesting that dnase2b is not expressed in the critical period for lens nuclear degradation, which corresponds to 56-74 hpf. However, public database searches have indicated that dnase1l3l is strongly and specifically expressed in embryonic zebrafish lens. Whole mount in situ hybridization showed that dnase1l3l expression began around 36 hpf and was found exclusively in the lens until the adult stage. Morpholino (MO)-dependent downregulation of dnase1l3l expression during early development in zebrafish led to the failure of nuclear degradation in the lens. Immunostaining of lens sections showed that expression of Pax6, Prox1 and ß-catenin was comparable to the control in the early stage of development in dnase1l3l-MO injected embryos. However, downregulation of expression of these genes in lens was not observed in dnase1l3l-MO-treated zebrafish at 72 hpf, suggesting that the lens development was halted. Taken together, we showed that dnase1l3l plays major roles in nuclear degradation in zebrafish lens development. No homologous gene was found in other species in public databases, suggesting that dnase1l3l developed and acquired its function specifically in zebrafish.

Identification of two Wnt-responsive elements in the intron of RING finger protein 43 (RNF43) gene.

RING finger protein 43 (RNF43), an E3-type ubiquitin ligase, is frequently up-regulated in human colorectal cancer. It has been shown that expression of RNF43 is regulated by the Wnt-signaling pathway. However the regulatory region(s) for its transcriptional activation has not been clarified. In this study, we have shown for the first time that RNF43 is a direct target of TCF4/ß-catenin complex, and that its expression is regulated by a regulatory region containing two Wnt-responsive elements (WREs) in intron2. A reporter gene assay revealed that nucleotide substitutions in the WREs decreased the reporter activity in colon cancer cells, suggesting that both WREs are involved in the transcriptional activation. Knockdown of ß-catenin by siRNA suppressed the reporter activity. In addition, ChIP assay showed that both elements associate with TCF4/ß-catenin complex in colon cancer cells. These data indicate that expression of RNF43 is regulated by the canonical Wnt/ß-catenin pathway through binding of the WREs with TCF4/ß-catenin complex. These findings should be useful for the understanding of the regulatory mechanism of RNF43 and may contribute to the clarification of signaling pathways regulated by RNF43.

Overexpression of cohesion establishment factor DSCC1 through E2F in colorectal cancer.

Ctf18-replication factor C complex including Dscc1 (DNA replication and sister chromatid cohesion 1) is implicated in sister chromatid cohesion, DNA replication, and genome stability in S. cerevisiae and C. elegans. We previously performed gene expression profiling in primary colorectal cancer cells in order to identify novel molecular targets for the treatment of colorectal cancer. A feature of the cancer-associated transcriptional signature revealed from this effort is the elevated expression of the proto-oncogene DSCC1. Here, we have interrogated the molecular basis for deviant expression of human DSCC1 in colorectal cancer and its ability to promote survival of cancer cells. Quantitative PCR and immunohistochemical analyses corroborated that the expression level of DSCC1 is elevated in 60-70% of colorectal tumors compared to their matched noncancerous colonic mucosa. An in silico evaluation of the presumptive DSCC1 promoter region for consensus DNA transcriptional regulatory elements revealed a potential role for the E2F family of DNA-binding proteins in controlling DSCC1 expression. RNAi-mediated reduction of E2F1 reduced expression of DSCC1 in colorectal cancer cells. Gain- and loss-of-function experiments demonstrated that DSCC1 is involved in the viability of cancer cells in response to genotoxic stimuli. We reveal that E2F-dependent expression of DSCC1 confers anti-apoptotic properties in colorectal cancer cells, and that its suppression may be a useful option for the treatment of colorectal cancer.

[Anesthetic and perioperative management of a patient with uncontrolled thyrotoxicosis undergoing coronary artery bypass grafting surgery].

Uncontrolled hyperthyroidism is a risk factor of perioperative thyrotoxic crisis. We report a case of a 61-year-old woman with thyrotoxicosis diagnosed with unstable angina pectoris. She needed to have an early scheduled coronay artery bypass grafting surgery, because percutaneous intervention for the left main coronary artery in support of intra-aortic balloon pumping (IABP) resulted in failure. Tachycardia and hyperthermia were observed at admission to the ICU, and hemodynamic parameters suggested high-output heart failure. Preoperative management using antithyroid drug, inorganic iodine, corticosteroid and propranolol stabilized her hemodynamic condition, and then CABG was performed on ICU day 3. Intraoperative and postoperative use of landiolol, a short acting beta blocker, was useful for maintaining hemodynamic stability. Surgery was uneventfully completed and she was extubated on postoperative day 1 following IABP withdrawal. Appropriate preoperative management and perioperative use of the short acting beta blocker were useful for management of the patient with uncontrolled hyperthyroid state.

Smyd3 is required for the development of cardiac and skeletal muscle in zebrafish.

Modifications of histone tails are involved in the regulation of a wide range of biological processes including cell cycle, cell survival, cell division, and cell differentiation. Among the modifications, histone methylation plays a critical role in cardiac and skeletal muscle differentiation. In our earlier studies, we found that SMYD3 has methyltransferase activity to histone H3 lysine 4, and that its up-regulation is involved in the tumorigenesis of human colon, liver, and breast. To clarify the role of Smyd3 in development, we have studied its expression patterns in zebrafish embryos and the effect of its suppression on development using Smyd3-specific antisense morpholino-oligonucleotides. We here show that transcripts of smyd3 were expressed in zebrafish embryos at all developmental stages examined and that knockdown of smyd3 in embryos resulted in pericardial edema and defects in the trunk structure. In addition, these phenotypes were associated with abnormal expression of three heart-chamber markers including cmlc2, amhc and vmhc, and abnormal expression of myogenic regulatory factors including myod and myog. These data suggest that Smyd3 plays an important role in the development of heart and skeletal muscle.

MRG-binding protein contributes to colorectal cancer development.

MRGBP (MORF4-related gene-binding protein; also known as chromosome 20 open reading frame 20) encodes a subunit of the transformation/transcription domain-associated protein (TRRAP)/tat-interacting protein 60 (TIP60)-containing histone acetyltransferase complex. We previously showed that MRGBP was upregulated in the majority of colorectal tumors, and the enhanced expression was associated with cell proliferation. In this study, we investigated its role in colorectal carcinogenesis and searched for genes regulated by MRGBP. Immunohistochemical staining of 22 adenomas and 47 carcinomas in the colon and rectum showed that high levels of MRGBP expression were observed more frequently in carcinomas (45%) than adenomas (5%), linking its role to malignant properties of colorectal tumors. No clinicopathological factors were associated with the levels MRGBP expression in colorectal cancer. Copy number analysis revealed that gene amplification is involved in the elevated expression. A genome-wide expression analysis identified a total of 41 genes upregulated by MRGBP. These genes were implicated in biological processes, including DNA replication, minichromosome maintenance, and cell division. Theses results suggest that MRGBP contributes to colorectal carcinogenesis through rendering advantages in cell proliferation and/or division of cancer cells. Our findings might be helpful for the identification of a specific biomarker for colorectal cancer and the development of diagnostic and/or therapeutic approaches.

Gasdermin D (Gsdmd) is dispensable for mouse intestinal epithelium development.

Members of the novel gene family Gasdermin (Gsdm) are exclusively expressed in a highly tissue-specific manner in the epithelium of skin and the gastrointestinal tract. Based on their expression patterns and the phenotype of the Gsdma3 spontaneous mutations, it is inferred that the Gsdm family genes are involved in epithelial cell growth and/or differentiations in different tissues. To investigate possible roles of the Gsdm gene family in the development of intestinal tracts, we generated a Gsdmd mutant mouse, which is a solitary member of the Gsdmd subfamily and which is predominantly expressed in the intestinal tract by means of targeted disruption. In the mutant homozygotes, we found no abnormality of intestinal tract morphology. Moreover, in mutant mice, there was normal differentiation of all constituent cell types of the intestinal epithelium. Thus, this study clearly shows that Gsdmd is not essential for development of mouse intestinal tract or epithelial cell differentiation.