Spliceosome-targeted therapies trigger an antiviral immune response in triple-negative breast cancer.

Many oncogenic insults deregulate RNA splicing, often leading to hypersensitivity of tumors to spliceosome-targeted therapies (STTs). However, the mechanisms by which STTs selectively kill cancers remain largely unknown. Herein, we discover that mis-spliced RNA itself is a molecular trigger for tumor killing through viral mimicry. In MYC-driven triple-negative breast cancer, STTs cause widespread cytoplasmic accumulation of mis-spliced mRNAs, many of which form double-stranded structures. Double-stranded RNA (dsRNA)-binding proteins recognize these endogenous dsRNAs, triggering antiviral signaling and extrinsic apoptosis. In immune-competent models of breast cancer, STTs cause tumor cell-intrinsic antiviral signaling, downstream adaptive immune signaling, and tumor cell death. Furthermore, RNA mis-splicing in human breast cancers correlates with innate and adaptive immune signatures, especially in MYC-amplified tumors that are typically immune cold. These findings indicate that dsRNA-sensing pathways respond to global aberrations of RNA splicing in cancer and provoke the hypothesis that STTs may provide unexplored strategies to activate anti-tumor immune pathways.

Inhibition of YTHDF2 triggers proteotoxic cell death in MYC-driven breast cancer.

RNA-binding proteins (RBPs) are critical regulators of post-transcriptional gene expression, and aberrant RBP-RNA interactions can promote cancer progression. Here, we interrogate the function of RBPs in cancer using pooled CRISPR-Cas9 screening and identify 57 RBP candidates with distinct roles in supporting MYC-driven oncogenic pathways. We find that disrupting YTHDF2-dependent mRNA degradation triggers apoptosis in triple-negative breast cancer (TNBC) cells and tumors. eCLIP and m6A sequencing reveal that YTHDF2 interacts with mRNAs encoding proteins in the MAPK pathway that, when stabilized, induce epithelial-to-mesenchymal transition and increase global translation rates. scRibo-STAMP profiling of translating mRNAs reveals unique alterations in the translatome of single cells within YTHDF2-depleted solid tumors, which selectively contribute to endoplasmic reticulum stress-induced apoptosis in TNBC cells. Thus, our work highlights the therapeutic potential of RBPs by uncovering a critical role for YTHDF2 in counteracting the global increase of mRNA synthesis in MYC-driven breast cancers.

Cost analysis of telemedicine use in paediatric nephrology-the LMIC perspective.

BACKGROUND: The overall cost of managing chronic diseases is a significant barrier to accessing complete and timely healthcare, especially in rural and geographically isolated areas. This cost disparity becomes more pronounced in the case of children and more so in under-resourced regions of the world. In the era of COVID-19, as the need for physical distancing increased, there was a transition in approach to healthcare provision to telemedicine consultations. This study evaluates the cost saving using teleconsultations in a paediatric nephrology clinic. METHODS: This prospective cohort study was conducted at AIIMS Jodhpur, a tertiary care centre in western Rajasthan from March 2021 to October 2022. All consecutive paediatric (29 days-18 years) patients attending telemedicine services for kidney-related illness were enrolled. Basic demographic details were collected. Cost analysis was done after 6 months, regarding perceived cost savings for the patient and family by using telehealth for follow-up during 6 months starting from enrolment. RESULTS: A total of 112 patients were enrolled; 266 teleconsultations attended; 109 patients who could be followed up saved INR 457,900 during 6 months of follow-up. The average cost saving was INR - 1577/patient/visit. Patients saved 4.99% of the family income (median 2.16% (IQR 0.66-5.5)). The highest expenditure per visit was incurred for food and transport. The median distance from the residence to the clinic was 122.5 km (IQR 30-250). Over the 6-month study period, patients saved a travel distance of 83,274 km (743 km/patient). CONCLUSIONS: The use of telemedicine as a follow-up method helps save significant costs and distances travelled by patients. A higher-resolution version of the Graphical abstract is available as Supplementary information.

Telomerase abrogates aneuploidy-induced telomere replication stress, senescence and cell depletion.

The causal role of aneuploidy in cancer initiation remains under debate since mutations of euploidy-controlling genes reduce cell fitness but aneuploidy strongly associates with human cancers. Telomerase activation allows immortal growth by stabilizing telomere length, but its role in aneuploidy survival has not been characterized. Here, we analyze the response of primary human cells and murine hematopoietic stem cells (HSCs) to aneuploidy induction and the role of telomeres and the telomerase in this process. The study shows that aneuploidy induces replication stress at telomeres leading to telomeric DNA damage and p53 activation. This results in p53/Rb-dependent, premature senescence of human fibroblast, and in the depletion of hematopoietic cells in telomerase-deficient mice. Endogenous telomerase expression in HSCs and enforced expression of telomerase in human fibroblasts are sufficient to abrogate aneuploidy-induced replication stress at telomeres and the consequent induction of premature senescence and hematopoietic cell depletion. Together, these results identify telomerase as an aneuploidy survival factor in mammalian cells based on its capacity to alleviate telomere replication stress in response to aneuploidy induction.

CEBP factors regulate telomerase reverse transcriptase promoter activity in whey acidic protein-T mice during mammary carcinogenesis.

Telomerase is activated in the majority of invasive breast cancers, but the time point of telomerase activation during mammary carcinogenesis is not clear. We have recently presented a transgenic mouse model to study human telomerase reverse transcriptase (TERT) gene expression in vivo (hTERTp-lacZ). In the present study, hTERTp-lacZxWAP-T bitransgenic mice were generated to analyze the mechanisms responsible for human and mouse TERT upregulation during tumor progression in vivo. We found that telomerase activity and TERT expression were consistently upregulated in SV40-induced invasive mammary tumors compared to normal and hyperplastic tissues and ductal carcinoma in situ (DCIS). Human and mouse TERT genes are regulated similarly in the breast tissue, involving the CEBP transcription factors. Loss of CEBP-α and induction of CEBP-ß expression correlated well with the activation of TERT expression in mouse mammary tumors. Transfection of CEBP-α into human or murine cells resulted in TERT repression, whereas knockdown of CEBP-α in primary human mammary epithelial cells resulted in reactivation of endogenous TERT expression and telomerase activity. Conversely, ectopic expression of CEBP-ß activated endogenous TERT gene expression. Moreover, ChIP and EMSA experiments revealed binding of CEBP-α and CEBP-ß to human TERT-promoter. This is the first evidence indicating that CEBP-α and CEBP-ß are involved in TERT gene regulation during carcinogenesis.

Mortality in Two Waves of COVID-19: A Comparative Analysis of a Tertiary Care Hospital in India.

Background COVID-19 has spread as two distinct surges of cases in many countries. Several countries have reported differences in disease severity and mortality in the two waves. Objective Compare the in-hospital mortality in the two COVID-19 waves at a tertiary care hospital in India. Methods We conducted a retrospective data collection. Distinct periods of surges in cases and admissions were defined as the first wave spanning from March 2020 to December 2020 and the second wave from April 2021 to June 21, 2021. The primary outcome of this study was to compare mortality rates in terms of total hospital mortality rate (TMR) and case fatality rate (CFR). Results Mortality rates of wave 2 were approximately 10 times that of wave 1 (TMR of 20.3% in wave 2 versus 2.4% in wave 1 and CFR of 1.5% versus 17.7% in wave 1 and 2, respectively). Mortalities in wave 2 had a larger proportion of severe disease at presentation, faster progression of symptoms to death, and more patients without any chronic comorbid condition dying due to the direct effect of COVID-19 acute respiratory distress syndrome (ARDS). Conclusion Our data matches the worldwide reported pooled hospital mortality figures and shows the comparative difference in disease severity between the two waves.

The promoter of human telomerase reverse transcriptase is activated during liver regeneration and hepatocyte proliferation.

BACKGROUND & AIMS: Telomerase activity has not been detected in healthy human liver biopsy samples, but it is up-regulated in most human liver tumors. It is not clear whether telomerase is activated in response to acute or chronic liver injury. Telomerase activity is closely associated with expression of its catalytic subunit, telomerase reverse transcriptase (TERT). We analyzed the activity of the human TERT (hTERT) promoter during liver regeneration in vivo and hepatocyte proliferation in vitro. METHODS: We used hTERTp-lacZ transgenic mice, which contain an 8.0-kilobase pair fragment of the hTERT gene promoter, to study the role of TERT in liver regeneration following partial hepatectomy. As an in vitro model, we used the HepaRG cell line as a new model system for human hepatocyte proliferation and differentiation. RESULTS: Activity of the hTERT promoter increased significantly after partial hepatectomy; it was also induced in hepatocytes, based on immunohistologic analysis. Similar to the in vivo results, telomerase activity and hTERT expression were up-regulated in proliferating HepaRG cells and repressed in response to growth arrest and differentiation. Promoter mapping revealed that a proximal 0.3-kilobase pair fragment contains all elements necessary for regulation of hTERT in HepaRG cells. We identified E2F2 and E2F7 as transcription factors that control the differential expression of hTERT in proliferating hepatocytes, in vitro and in vivo. CONCLUSIONS: hTERT is induced in hepatocytes during liver regeneration, indicating a functional role for telomerase in human liver.

Comparison between C-MAC and King Vision video laryngoscope (channelled blade) for tracheal intubation in aerosol-prevention intubation box for COVID-19 patients: A manikin-based study.

Background and Aims: The risk of contracting infection while intubating a coronavirus disease 2019 (COVID-19)-positive patient can be reduced by the use of personal protective equipment (PPE), video laryngoscope (VL) and aerosol-preventing intubation box. We compared two VLs (C-MAC and King Vision laryngoscope [KVL]) for ease of intubation and time taken to intubate the manikin using an intubation box. Methods: This randomised study involved healthcare workers having experience in using both C-MAC and KVL. After explaining the study and five practice sessions, a total of 63 volunteers were included; 61 participants gave consent and were enroled. The participants were allowed to intubate initially with one VL as per random sequence. Each participant performed three tracheal intubations with each device (C-MAC VL and KVL) on a manikin using an aerosol-prevention box over the head end at the time of intubation. Results: Time taken, percentage of glottic opening (POGO) score and the number of attempts taken for successful intubation with C-MAC and KVL were comparable in any of the three attempts (P > 0.05). The participants reported more difficulty in using KVL compared to C-MAC, and insertion of laryngoscope blade into the mouth of manikin for intubation was easy in group C-MAC compared to KVL in all three intubations (P < 0.01). Conclusion: C-MAC and KVL take comparable time for successful intubation under COVID-19 simulation conditions. But C-MAC is more user-friendly.

A Correlation Analysis of Peripheral Oxygen Saturation and Arterial Oxygen Saturation Among COVID-19 Patients.

Background and objective It has been observed that peripheral oxygen saturation (SpO2) measured by pulse oximeter is consistently lower than arterial oxygen saturation (SaO2) measured directly by blood gas analysis. In this study, we aimed to evaluate the correlation between SpO2 and SaO2, and SpO2 and partial pressure of oxygen (PaO2), and compare the SpO2/FiO2 (SF) and PaO2/FiO2 (PF) ratios in patients with coronavirus disease 2019 (COVID-19). Methods In this observational study, SpO2 was recorded and arterial blood gas analysis was performed among 70 COVID-19 patients presenting on room air (FiO2 = 0.21). SaO2 and PaO2 were recorded from arterial blood gas analysis. The SF and PF ratios were then calculated. Results The strength of correlations between SpO2 and SaO2, and SpO2 and PaO2, were significant (p<0.001) and moderately positive [Pearson coefficient (r) = 0.68, 0.53]. SpO2 value (85%), i.e., SF ratio (404.7 or below), was the best estimate for mild ARDS (acute respiratory distress syndrome) [PF ratio (300 or below)] with a sensitivity of 80.6% and specificity of 53%. Conclusion A pulse oximeter is a vital tool in the diagnosis and management of COVID-19. In our study, SpO2 was found to have a positive correlation with SaO2 and PaO2 with acceptable sensitivity but low specificity in estimating mild ARDS. Therefore, pulse oximetry can be used as a tool for the early diagnosis of mild COVID-19 ARDS as per the given considerations and clinical correlation.

Aneuploidy-inducing gene knockdowns overlap with cancer mutations and identify Orp3 as a B-cell lymphoma suppressor.

Aneuploidy can instigate tumorigenesis. However, mutations in genes that control chromosome segregation are rare in human tumors as these mutations reduce cell fitness. Screening experiments indicate that the knockdown of multiple classes of genes that are not directly involved in chromosome segregation can lead to aneuploidy induction. The possible contribution of these genes to cancer formation remains yet to be defined. Here we identified gene knockdowns that lead to an increase in aneuploidy in checkpoint-deficient human cancer cells. Computational analysis revealed that the identified genes overlap with recurrent mutations in human cancers. The knockdown of the three strongest selected candidate genes (ORP3, GJB3, and RXFP1) enhances the malignant transformation of human fibroblasts in culture. Furthermore, the knockout of Orp3 results in an aberrant expansion of lymphoid progenitor cells and a high penetrance formation of chromosomal instable, pauci-clonal B-cell lymphoma in aging mice. At pre-tumorous stages, lymphoid cells from the animals exhibit deregulated phospholipid metabolism and an aberrant induction of proliferation regulating pathways associating with increased aneuploidy in hematopoietic progenitor cells. Together, these results support the concept that aneuploidy-inducing gene deficiencies contribute to cellular transformation and carcinogenesis involving the deregulation of various molecular processes such as lipid metabolism, proliferation, and cell survival.

Protect the Protector: Morbidity and Health Behavior among Police Personnel in National Capital Region of India.

INTRODUCTION: At the time of selection, police personnel undergo various health and fitness tests but subsequently health assessments are not done regularly. Unhealthy lifestyle and challenging work environment predispose them to various somatic sequelae, including cardiovascular diseases, musculoskeletal, gastrointestinal, and psychological disorders, etc., There is limited epidemiological data on the morbidity profile among police personnel in India. AIM: To study the morbidity profile and the treatment-seeking behavior among police personnel in National Capital Region (NCR), India. MATERIALS AND METHODS: A cross-sectional study was conducted between May and November, 2014 on 300 police personnel working in the NCR, India. We administered a predesigned, pretested questionnaire (α = 0.63) to the study participants based on World Health Organization-STEPS tool for assessing morbidity profile, lifestyle risk factors, and treatment-seeking behavior after obtaining informed consent from the study participants. RESULTS: Health complaints were reported by around half (n = 149, 49.6%) of the participants with the morbidity risk of 0.71 per person. The most common complaints were related to the cardiovascular and musculoskeletal system. Only around half of the affected participants took any treatment. Hospitalization rate reflected from past 1-year hospital admissions among participants was (n = 23, 7.7%). Data analysis suggested morbidity status of police personnel to be significantly associated with lifestyle risk factors such as abdominal obesity (n = 129, 86.5%), obstructive sleep apnea (n = 54, 36.2%), and distress (n = 48, 32.2%). CONCLUSION: Busy and challenging work life and poor control of health lead to high morbidity among police personnel. Regular health checks and lifestyle promotional activities are highly recommended to maintain a healthy police force.

Telomerase stimulates ribosomal DNA transcription under hyperproliferative conditions.

In addition to performing its canonical function, Telomerase Reverse Transcriptase (TERT) has been shown to participate in cellular processes independent of telomerase activity. Furthermore, although TERT mainly localizes to Cajal bodies, it is also present within the nucleolus. Because the nucleolus is the site of rDNA transcription, we investigated the possible role of telomerase in regulating RNA polymerase I (Pol I). Here we show that TERT binds to rDNA and stimulates transcription by Pol I during liver regeneration and Ras-induced hyperproliferation. Moreover, the inhibition of telomerase activity by TERT- or TERC-specific RNA interference, the overexpression of dominant-negative-TERT, and the application of the telomerase inhibitor imetelstat reduce Pol I transcription and the growth of tumour cells. In vitro, telomerase can stimulate the formation of the transcription initiation complex. Our results demonstrate how non-canonical features of telomerase may direct Pol I transcription in oncogenic and regenerative hyperproliferation.