Dual inhibition of SUMOylation and MEK conquers MYC-expressing KRAS-mutant cancers by accumulating DNA damage.

BACKGROUND: KRAS mutations frequently occur in cancers, particularly pancreatic ductal adenocarcinoma, colorectal cancer, and non-small cell lung cancer. Although KRASG12C inhibitors have recently been approved, effective precision therapies have not yet been established for all KRAS-mutant cancers. Many treatments for KRAS-mutant cancers, including epigenome-targeted drugs, are currently under investigation. Small ubiquitin-like modifier (SUMO) proteins are a family of small proteins covalently attached to and detached from other proteins in cells via the processes called SUMOylation and de-SUMOylation. We assessed whether SUMOylation inhibition was effective in KRAS-mutant cancer cells. METHODS: The efficacy of the first-in-class SUMO-activating enzyme E inhibitor TAK-981 (subasumstat) was assessed in multiple human and mouse KRAS-mutated cancer cell lines. A gene expression assay using a TaqMan array was used to identify biomarkers of TAK-981 efficacy. The biological roles of SUMOylation inhibition and subsequent regulatory mechanisms were investigated using immunoblot analysis, immunofluorescence assays, and mouse models. RESULTS: We discovered that TAK-981 downregulated the expression of the currently undruggable MYC and effectively suppressed the growth of MYC-expressing KRAS-mutant cancers across different tissue types. Moreover, TAK-981-resistant cells were sensitized to SUMOylation inhibition via MYC-overexpression. TAK-981 induced proteasomal degradation of MYC by altering the balance between SUMOylation and ubiquitination and promoting the binding of MYC and Fbxw7, a key factor in the ubiquitin-proteasome system. The efficacy of TAK-981 monotherapy in immunocompetent and immunodeficient mouse models using a mouse-derived CMT167 cell line was significant but modest. Since MAPK inhibition of the KRAS downstream pathway is crucial in KRAS-mutant cancer, we expected that co-inhibition of SUMOylation and MEK might be a good option. Surprisingly, combination treatment with TAK-981 and trametinib dramatically induced apoptosis in multiple cell lines and gene-engineered mouse-derived organoids. Moreover, combination therapy resulted in long-term tumor regression in mouse models using cell lines of different tissue types. Finally, we revealed that combination therapy complementally inhibited Rad51 and BRCA1 and accumulated DNA damage. CONCLUSIONS: We found that MYC downregulation occurred via SUMOylation inhibition in KRAS-mutant cancer cells. Our findings indicate that dual inhibition of SUMOylation and MEK may be a promising treatment for MYC-expressing KRAS-mutant cancers by enhancing DNA damage accumulation.

Targeting WEE1 enhances the antitumor effect of KRAS-mutated non-small cell lung cancer harboring TP53 mutations.

The clinical development of Kirsten rat sarcoma virus (KRAS)-G12C inhibitors for the treatment of KRAS-mutant lung cancer is limited by the presence of co-mutations, intrinsic resistance, and the emergence of acquired resistance. Therefore, innovative strategies for enhancing apoptosis in KRAS-mutated non-small cell lung cancer (NSCLC) are urgently needed. Through CRISPR-Cas9 knockout screening using a library of 746 crRNAs and drug screening with a custom library of 432 compounds, we discover that WEE1 kinase inhibitors are potent enhancers of apoptosis, particularly in KRAS-mutant NSCLC cells harboring TP53 mutations. Mechanistically, WEE1 inhibition promotes G2/M transition and reduces checkpoint kinase 2 (CHK2) and Rad51 expression in the DNA damage response (DDR) pathway, which is associated with apoptosis and the repair of DNA double-strand breaks, leading to mitotic catastrophe. Notably, the combined inhibition of KRAS-G12C and WEE1 consistently suppresses tumor growth. Our results suggest targeting WEE1 as a promising therapeutic strategy for KRAS-mutated NSCLC with TP53 mutations.

Case report: Navigating treatment pathways for cardiac intimal sarcoma with PDGFRß N666K mutation.

In the realm of rare cardiac tumors, intimal sarcoma presents a formidable challenge, often requiring innovative treatment approaches. This case report presents a unique instance of primary intimal sarcoma in the left atrium, underscoring the critical role of genomic profiling in guiding treatment. Initial genomic testing unveiled a somatic, active mutation in PDGFRß (PDGFRß N666K), accompanied by MDM2 and CDK4 amplifications. This discovery directed the treatment course toward pazopanib, a PDGFRß inhibitor, following irradiation. The patient's response was remarkable, with the therapeutic efficacy of pazopanib lasting for 16.3 months. However, the patient experienced a recurrence in the left atrium, where subsequent genomic analysis revealed the absence of the PDGFRß N666K mutation and a significant reduction in PDGFRß expression. This case report illustrates the complexities and evolving nature of cardiac intimal sarcoma treatment, emphasizing the potential of PDGFRß signaling as a strategic target and highlighting the importance of adapting treatment pathways in response to genetic shifts.

Evaluation of two semi-supervised learning methods and their combination for automatic classification of bone marrow cells.

Differential bone marrow (BM) cell counting is an important test for the diagnosis of various hematological diseases. However, it is difficult to accurately classify BM cells due to non-uniformity and the lack of reproducibility of differential counting. Therefore, automatic classification systems have been developed in which deep learning is used. These systems requires large and accurately labeled datasets for training. To overcome this, we used semi-supervised learning (SSL), in which learning proceeds while labeling. We used three methods: self-training (ST), active learning (AL), and a combination of these methods, and attempted to automatically classify 16 types of BM cell images. ST involves data verification, as in AL, before adding them to the training dataset (confirmed self-training: CST). After 25 rounds of CST, AL, and CST + AL, the initial number of training data increased from 425 to 40,518; 3682; and 47,843, respectively. Accuracies for the test data of 50 images for each cell type were 0.944, 0.941, and 0.976, respectively. Data added with CST or AL showed some imbalances between classes, while CST + AL exhibited fewer imbalances. We suggest that CST + AL, when combined with two SSL methods, is efficient in increasing training data for the development of automatic BM cells classification systems.

Mediastinal Malignant Melanoma Markedly Shrinking in Response to Nivolumab.

Primary malignant melanoma (MM) of the mediastinum is rare, and there is a lack of consensus regarding the preferred treatment because non-cutaneous MM demonstrates an inferior response to systemic therapy. Herein, we describe the case of a 73-year-old man with MM of the anterior mediastinum with multiple liver metastases. Even though the size of lesions increased rapidly following diagnosis, nivolumab monotherapy caused remarkable tumor shrinkage. This is the first report of mediastinal MM showing a significant response to nivolumab. We, therefore, suggest that immunotherapy may be one of the treatment options for primary mediastinal MM.

Multi-institutional survey of cancer disparities in disabled patients in the region of northwestern Japan.

BACKGROUND: Potential disparities between cancer patients with and without disabilities remained to be validate in Japan. METHODS: We surveyed retrospective data on hospital cancer registration as well as information on disability certificates obtained through the Hokushin Ganpro database. In total, 93,545 cancer patients in 10 principal hospitals covering the region of northwestern Japan were registered with the Hokushin Ganpro database between 2010 and 2015. The database included the following data: diagnosis date, cancer type, staging, treatment, cancer detection process, and possession of a disability certificate. RESULTS: We found that 2983 patients, which accounted for 3.2% of the total patients, had disabilities. No significant differences in gender, age at diagnosis, cancer stage distribution, and cancer incidence rates were observed between the disabled and non-disabled patients. Even though the proportion of early-stage cancer among disabled patients differed only slightly from that in non-disabled patients, early-stage cancer was more frequently diagnosed in patients with disabilities during their regular hospital visits than in those without disabilities, who had more opportunity for early cancer detection during cancer screening. According to in-house data reflecting treatment period and process from a single hospital, all 16 disabled patients treated with chemotherapy completed the treatment until disease progression or end of predetermined cycles. CONCLUSION: These results indicate that deep disparities between cancer patients with and without disabilities are not apparent and that the disabled patients in the region of northwestern Japan receive appropriate hospital follow-up.

Clinical outcome of patients with inoperable pancreatic cancer treated with FOLFIRINOX or gemcitabine plus Nab­paclitaxel as a first­line therapy: A retrospective analysis.

The present study aimed to evaluate the clinical benefits of leucovorin, 5-fluorouracil, irinotecan and oxaliplatin (FOLFIRINOX) vs. gemcitabine plus Nab-paclitaxel (GnP) as a first-line therapy for patients with inoperable pancreatic cancer. For this purpose, in-house data available for 45 patients who received FOLFIRINOX or GnP as first-line treatment between 2014 and 2019 were retrospectively analyzed. In total, 21 and 24 patients received FOLFIRINOX and GnP, respectively. Although there were no significant differences in the median progression-free survival, the median overall survival was longer in the FOLFIRINOX group than in the GnP group (16.7 vs. 7.2 months). A total of 14 patients received FOLFIRINOX followed by GnP, whereas 3 patients received GnP followed by FOLFIRINOX. All patients who did not switch to second-line therapy owing to poor feasibility were included in the GnP group. The data indicated that patients receiving GnP as first-line therapy were less likely to switch to FOLFIRINOX and, consequently, had a worse prognosis.

Development of stereotaxic recording system for awake marmosets (Callithrix jacchus).

The common marmoset has been proposed as a potential alternative to macaque monkey as a primate model for neuroscience and medical research. Here, we have newly developed a stereotaxic neuronal recording system for awake marmosets under the head-fixed condition by modifying that for macaque monkeys. Using this system, we recorded neuronal activity in the cerebral cortex of awake marmosets and successfully identified the primary motor cortex by intracortical microstimulation. Neuronal activities of deep brain structures, such as the basal ganglia, thalamus, and cerebellum, in awake marmosets were also successfully recorded referring to magnetic resonance images. Our system is suitable for functional mapping of the brain, since the large recording chamber allows access to arbitrary regions over almost the entire brain, and the recording electrode can be easily moved stereotaxically from one site to another. In addition, our system is desirable for neuronal recording during task performance to assess motor skills and cognitive function, as the marmoset sits in the marmoset chair and can freely use its hands. Moreover, our system can be used in combination with cutting-edge techniques, such as two-photon imaging and optogenetic manipulation. This recording system will contribute to boosting neuroscience and medical research using marmosets.

Optogenetic Activation of the Sensorimotor Cortex Reveals "Local Inhibitory and Global Excitatory" Inputs to the Basal Ganglia.

To understand how information from different cortical areas is integrated and processed through the cortico-basal ganglia pathways, we used optogenetics to systematically stimulate the sensorimotor cortex and examined basal ganglia activity. We utilized Thy1-ChR2-YFP transgenic mice, in which channelrhodopsin 2 is robustly expressed in layer V pyramidal neurons. We applied light spots to the sensorimotor cortex in a grid pattern and examined neuronal responses in the globus pallidus (GP) and entopeduncular nucleus (EPN), which are the relay and output nuclei of the basal ganglia, respectively. Light stimulation typically induced a triphasic response composed of early excitation, inhibition, and late excitation in GP/EPN neurons. Other response patterns lacking 1 or 2 of the components were also observed. The distribution of the cortical sites whose stimulation induced a triphasic response was confined, whereas stimulation of the large surrounding areas induced early and late excitation without inhibition. Our results suggest that cortical inputs to the GP/EPN are organized in a "local inhibitory and global excitatory" manner. Such organization seems to be the neuronal basis for information processing through the cortico-basal ganglia pathways, that is, releasing and terminating necessary information at an appropriate timing, while simultaneously suppressing other unnecessary information.

[Future Images of General Hospital Psychiatry].

Now, the psychiatric departments of general hospitals are unpopular workplaces for psy- chiatrists in Japan. However, I think there is a constant need for psychiatric departments of general hospitals, because the number of psychiatric departments of general hospitals with no psychiatric beds is increasing, even though the number of psychiatric departments of general hospitals with psychiatric beds is decreasing. Recently, there has been a trend of reevaluating psychiatry in medical care, such as in the medical treatments fees or in health care planning, so we cannot talk about medical care without involving psychiatry. The participation of gen- eral hospital psychiatry with a medical cooperation function is necessary for psychiatric reform from hospital-based to community-based psychiatry, as well as for the promotion of self-suffi- cient medical care in local communities based on medical cooperation. For psychiatry corre- sponding to high-grade acute medical care, the existence of general hospital psychiatry is nec- essary which has close contact with medical care and has a psychiatric acute care function, and adequate measures should be adopted in the national medical care fee and medical policies for the enhancement of general hospital psychiatry.

[The Report of the Survey to the Members of the Society about the Functional Dissociation of the Psychiatric Hospital beds].

In 2014, Japanese Ministry of Health, Labour and Welfare published the guideline on the policy of the psychiatric hospitals. We executed a survey to the members of "The Japanese Society of Psychiatry and Neurology" about the impression of this guideline, especially about "The functional differentiation of psychiatric hospital beds". Nine questions were notified on the home page of the society. 862 answers (5.3% of the members) were corrected by website from 1st to 30th of May in 2015. Attribution of the answers : doctors working at the psychiatric hospitals (70.9%), the psychiatric clinics (20%), the others (9.1%). The questions which more than 80% of the answers agreed were "The reduction of the psychiatric beds should be stepwise under the rule of check & balance in the improvement of the psychiatric community treatment", "Improve the function of the recovery phase treatment" and "The adequate treat- ment for the patients of the severe and chronic phases". The questions more than 55% of the answers agreed were "The reduction of the chronic phase beds for the improvement of the function of the acute phase beds". The questions which opposites exceeded (almost 47%) were "The assessment of the psychiatric symptoms in the patients of the chronic phase should be done by the third party" and "The facility for social skill treatment should be placed in the community". We could know the mind of the members about the revolution of the psychiatric.

Prevalence, course and factors associated with delirium in elderly patients with advanced cancer: a longitudinal observational study.

OBJECTIVE: The aim of this study was to investigate the prevalence of delirium on admission, the course of delirium during a 2-week period after admission and factors associated with delirium on admission, among elderly patients with advanced cancer. METHODS: Patients aged ≥ 65 years with incurable lung or gastroenterological cancer and the Eastern Cooperative Oncology Group Performance Status 2 or greater were continuously sampled after admission to a university hospital. Participants were evaluated for DSM-IV-TR delirium by trained psychiatrists and the delirium subtype was assessed using the Delirium Motor Subtype Scale within 4 days after admission and again 2 weeks later. In addition, we assessed associated factors with delirium on admission. RESULTS: Among 73 eligible patients, complete data were available from 61 on admission and 49 after 2 weeks. Twenty-six patients (43%) met delirium criteria on admission (hypoactive: 58%, unspecified: 35%, hyperactive: 4%, mixed: 4%). Of these, 19 (73%) remained delirious 2 weeks later. Of 35 patients without delirium on admission, 21 (60%) remained delirium-free 2 weeks later and 7(20%) became delirious. Overall, 33/61 (54%) developed delirium at some point during the study. Patients receiving steroids at admission were more likely to have delirium (odds ratio = 5.0; 95% confidence interval = 1.5-16). CONCLUSIONS: Given the high prevalence of the delirium, all patients with advanced cancer should be screened for delirium both on admission and regularly thereafter. In addition, medical staff should be aware that steroid use on admission is an additional indicator of elevated risk for delirium.

Complications associated with endobronchial ultrasound-guided transbronchial needle aspiration: a nationwide survey by the Japan Society for Respiratory Endoscopy.

BACKGROUND: With the recent widespread use of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA), there have been occasional reports on complications associated with its use. Previous reviews on EBUS-TBNA have been limited to studies by skilled operators, thus the results may not always be applicable to recent clinical practice. To assess the safety of EBUS-TBNA for the staging and diagnosis of lung cancer in Japan, a nationwide survey on its current usage status and complications associated with its use was conducted by the Japan Society for Respiratory Endoscopy (JSRE). METHODS: A questionnaire about EBUS-TBNA performed between January 2011 and June 2012 was mailed to 520 JSRE-accredited facilities. RESULTS: Responses were obtained from 455 facilities (87.5%). During the study period, EBUS-TBNA was performed in 7,345 cases in 210 facilities (46.2%) using a convex probe ultrasound bronchoscope, for 6,836 mediastinal and hilar lesions and 275 lung parenchymal lesions. Ninety complications occurred in 32 facilities. The complication rate was 1.23% (95% confidence interval, 0.97%-1.48%), with hemorrhage being the most frequent complication (50 cases, 0.68%). Infectious complications developed in 14 cases (0.19%) (Mediastinitis, 7; pneumonia, 4; pericarditis, 1; cyst infection, 1; and sepsis, 1). Pneumothorax developed in 2 cases (0.03%), one of which required tube drainage. Regarding the outcome of the cases with complications, prolonged hospitalization was observed in 14 cases, life-threatening conditions in 4, and death in 1 (severe cerebral infarction) (mortality rate, 0.01%). Breakage of the ultrasound bronchoscope occurred in 98 cases (1.33%) in 67 facilities (31.9%), and that of the puncture needle in 15 cases (0.20%) in 8 facilities (3.8%). CONCLUSIONS: Although the complication rate associated with EBUS-TBNA was found to be low, severe complications, including infectious complications, were observed, and the incidence of device breakage was high. Since the use of EBUS-TBNA is rapidly expanding in Japan, an educational program for its safe performance should be immediately established.

Bronchoscopic practice in Japan: a survey by the Japan Society for Respiratory Endoscopy in 2010.

BACKGROUND AND OBJECTIVE: To ensure the safety of bronchoscopic practice, the Japan Society for Respiratory Endoscopy conducted a national survey to investigate the current state of procedure for this technique. METHODS: A questionnaire survey about procedures carried out during the whole of the year 2010 was mailed to 538 facilities accredited by the society. RESULTS: Responses were obtained from 511 facilities (95.0%). Rigid bronchoscopes were used in only 18.5% of the facilities, while mobile/thin bronchoscopes were used in ≥ 50%, and fluoroscopy systems were used in 99.8%. Biopsies were performed after discontinuation of therapy in patients receiving antiplatelet drugs and anticoagulants in 96.7% and 97.4% of the facilities, respectively. Atropine was administered for premedication in 67.5% of the facilities, a decrease from previous surveys. Intravenous sedation was given in 36.1% of the facilities. In 21.9% of these, the procedure was conducted in the outpatient clinic for ≥ 70% of patients. A bronchoscope was orally inserted in ≥ 70% of patients in 95.7% of the facilities. Intravenous access was maintained during the examination in 92.5% of the facilities, oxygen saturation was monitored during examinations in 99.0%, oxygen was administered in 97.6% and resuscitation equipment was available in 96%. In 98.6% of the facilities, bronchoscopes were disinfected using an automatic washing machine, with glutaraldehyde used in 42.2%. CONCLUSIONS: Japan-specific characteristics of bronchoscopic practice were identified. Whether procedures used in Japan meet international guidelines with respect to safety should be monitored continuously. In addition, a Japanese evidence-based consensus is needed.

Diagnosis of ovarian cancers using thoracoscopy: Three case reports and review of the literature.

Thoracoscopy is a useful method for diagnosing plural lesions. We diagnosed 3 cases of ovarian adenocarcinoma by thoracoscopy. All patients were middle-aged and elderly women. Initial examination revealed intrathoracic lesions including pleural effusion, but intraperitoneal lesions were unclear. In all cases, adequate samples of tumor cells obtained using thoracoscopy were used in the identification of tumor origin. Elevated serum levels of cancer antigen 125 (CA-125) and Krebs von den lungen-6 (KL-6) were observed in 2 of the 3 patients. Diagnoses of ovarian cancer were based on immunohistochemical examinations and clinical course. This report describes the diagnostic usefulness of thoracoscopy and serum KL-6 in cases of ovarian cancer with predominantly intrathoracic lesions.

Preclinical rationale for synergistic interaction of pemetrexed and cytotoxic nucleoside analogues.

Cytotoxic nucleoside analogues are widely used in cancer chemotherapy. We used the cytosine arabinoside (Ara-C)-resistant erythroleukaemia cell line K562 and the Ara-C-sensitive myeloid leukaemia cell line HL60 to examine the differential expression of molecular markers. We found increased expression levels of deoxycytidine kinase (dCK) and human equilibrative nucleoside transporter 1 (hENT1) and decreased levels of multidrug resistance protein 5 (ABCC5) and ribonucleoside reductase subunit M1 (RRM1) expression in Ara-C-sensitive HL60 cells. We previously established the pemetrexed (MTA)-resistant small cell lung cancer cell lines PC6/MTA-0.4 and PC6/MTA-1.6 and found that MTA-resistant cells are more sensitive to gemcitabine (GEM) and Ara-C compared with parental PC-6 cells. We examined the molecular markers for GEM and Ara-C sensitivity in MTA-resistant cells and found increased gene expression of dCK and hENT1. Furthermore, treatment with MTA resulted in increased expression of dCK and hENT1 and decreased expression of ABCC5 and RRM1, concomitant with the alteration of the resistance to Ara-C in Ara-C-resistant K562 cells. These results provide evidence that the chemotherapeutic activity of the combination of MTA and cytotoxic nucleoside analogues is synergistic with regard to the alteration of metabolic molecules.

Selected polymorphisms of base excision repair genes and pancreatic cancer risk in Japanese.

BACKGROUND: Although several reports have described a possible association between DNA repair genes and pancreatic cancer (PC) in smokers, this association has not been fully evaluated in an Asian population. We assessed the impact of genetic polymorphisms in the base excision repair (BER) pathway on PC risk among Japanese. METHODS: This case-control study compared the frequency of 5 single-nucleotide polymorphisms (SNPs) of BER genes, namely rs1052133 in OGG1, rs1799782 and rs25487 in XRCC1, rs1130409 in APE1, and rs1136410 in PARP1. SNPs were investigated using the TaqMan assay in 185 PC cases and 1465 controls. Associations of PC risk with genetic polymorphisms and gene-environment interaction were examined with an unconditional logistic regression model. Exposure to risk factors was assessed from the results of a self-administered questionnaire. We also performed haplotype-based analysis. RESULTS: We observed that the minor allele of rs25487 in XRCC1 was significantly associated with PC risk in the per-allele model (odds ratio = 1.29, CI = 1.01-1.65; trend P = 0.043). Haplotype analysis of XRCC1 also showed a statistically significant association with PC risk. No statistically significant interaction between XRCC1 polymorphisms and smoking status was seen. CONCLUSIONS: Our findings suggest that XRCC1 polymorphisms affect PC risk in Japanese.

A case of carcinomatous meningitis despite prophylactic cranial irradiation in small cell lung cancer during treatment with amrubicin.

A 47-year-old man was diagnosed with limited-disease small cell lung cancer. Treatment was initiated with concurrent chemotherapy and radiotherapy. A partial response was achieved, and prophylactic cranial irradiation (PCI) was administered. Local recurrence was identified on follow-up and treated with amrubicin (AMR). After two courses of AMR, a state of stable disease was achieved and AMR treatment was continued. After the third course of AMR, the patient was urgently hospitalized suffering from a headache and disturbance of consciousness, and a diagnosis of carcinomatous meningitis was made. This case report concerns a case of carcinomatous meningitis despite PCI during treatment with AMR.