Numair Arshad
Content writer – Clinical
Clinical trial shows potential of poziotinib for HER2-mutant lung cancer.
Published on: September 13, 2023
Original author: Yasir Y. Elamin et al., 2022 (doi: 10.1200/JCO.21.01113)
Non-small cell lung cancer (NSCLC) is the most common type of lung cancer, accounting for up to 85% of the patients. Around 3% of these NSCLC patients have mutations in the human epidermal growth factor receptor 2 (ERBB2, HER2) gene. Currently approved targeted therapies, like afatinib or trastuzumab, are ineffective in HER2-mutated lung cancer. The standard of care in such patients is chemotherapy which may be combined with immunotherapy drugs. However, their efficacy is limited which has prompted the research for better ways to treat lung cancer patients harboring mutations in the HER2 gene. The clinical study that is the subject of this blog post is a phase 2 clinical trial aimed at evaluating the effects of a new targeted therapy drug, called poziotinib, for treating NSCLC patients with HER2 exon 20 mutations. Poziotinib is an orally available drug that targets the insertion mutations in the exon 20 of the HER2 gene. Preclinical studies have shown that poziotinib can potently inhibit tumor growth in HER2 mutant models. Methodology This single-center phase 2 trial enrolled 30 patients with metastatic (stage IV) or recurrent NSCLC with HER2 exon 20 mutations. The presence of HER2 exon mutations was confirmed through the genome sequencing clinical tests such as Oncomine Comprehensive Assay, Guardant360 Assay, or Foundation One Assay. Furthermore, the participants had to be at least 18 years old, adequate organ function, and disease measurable via commonly used imaging modalities for lung cancer such as computed tomography (CT), positron emission tomography (PET)-CT, or magnetic resonance imaging (MRI). Patients who received chemotherapy and other systemic therapies were allowed if those treatments were discontinued 14 days prior to the start of the clinical trial. Poziotinib was given orally to all the participants at a dose of 16 mg once daily in 28-day cycles. Tumor assessment was done every 8 weeks. Patients were allowed to continue taking poziotinib if showed clear benefit and there was no opposing factor such as poor compliance or adverse effects. The primary outcome was objective response rate (ORR) per RECIST criteria. Secondary outcomes included progression-free survival (PFS), duration of response (DOR), disease control rate, overall survival, and safety. Results The confirmed ORR was 27% and the median DOR was 5 months. An additional 46% of patients achieved stable disease. The median PFS was 5.5 months. In the 90% of patients with prior platinum chemotherapy, PFS was 5 months. The safety profile showed high rates of grade 3 skin rash (47%), diarrhea (20%), and paronychia (20%). For the majority of patients, adverse effects were manageable with dose reductions. However, only one patient discontinued poziotinib due to adverse effects. There was one possible treatment-related death from pneumonitis (inflammation of the lungs). Conclusion Poziotinib showed promising antitumor activity in advanced HER2 exon 20 mutant NSCLC, including patients previously treated with chemotherapy. The safety profile was consistent with other HER2/EGFR inhibitors, with skin and GI side effects. This study indicates poziotinib could be a new treatment option for NSCLC patients with HER2 mutations who have limited responses to other therapies. Impact of the research This study contributes to the ongoing research on treatment options for HER2-mutated NSCLC. Since HER2 exon 20 mutations cause resistance, poziotinib's ability to inhibit tumor growth highlights the importance of designing targeted therapies that overcome specific resistance mutations. More research is needed to target resistance-causing mutations in cancer.
Observation vs. radiosurgery: Which is best for asymptomatic meningiomas?
Published on: June 28, 2023
Original author: Sheehan et al., 2022 (doi: 10.1093/neuonc/noab132)
Meningiomas are the most common intracranial tumors, accounting for almost 30% of all central nervous system (CNS) tumors in adults. A great majority of meningiomas are benign, correlating to grade I of World Health Organization (WHO) classification. They are frequently detected by chance while being asymptomatic. The incidence of asymptomatic meningiomas is increasing due to the increased use of brain imaging. The optimal management of asymptomatic meningiomas is complicated. Observation with longitudinal surveillance is a common approach for smaller meningiomas, but over time, many tumors may grow and develop symptoms. But their surgical resection is associated with treatment-related neurological complications. Stereotactic radiosurgery (SRS) has emerged as a promising treatment option for asymptomatic meningiomas. SRS is a non-invasive procedure in which a highly precise beam of radiation is used to target the tumor. However, the decision to pursue SRS in asymptomatic meningiomas is not straightforward. It involves the consideration of the potential neurological complications and the overall survival benefit as compared to observation. The International Multicenter Matched Cohort Analysis of Incidental Meningioma Progression During Active Surveillance or After Stereotactic Radiosurgery (IMPASSE) study aimed to evaluate the efficacy and safety of SRS in the treatment of asymptomatic meningiomas. The study compared SRS outcomes to active surveillance of asymptomatic meningiomas and evaluated local tumor control and the development of new neurological deficits attributable to the tumor in both groups. Methodology The study included asymptomatic meningioma patients who were treated with SRS or observed over time and was conducted across 14 centers in 10 countries. The patients were diagnosed based on neuroimaging findings, and histology was limited to WHO grade I meningiomas. The primary endpoint was local control, defined as a stable or regressed tumor in neuroimaging studies based on Response Assessment in Neuro-Oncology (RANO) criteria. The secondary outcomes included tumor regression, tumor progression, tumor progression-free survival, and the development of a new neurological deficit. Tumor progression was defined as a tumor volume increase of ≥25% of its baseline. Tumor progression-free survival was measured in months based on the radiological follow-up. Patients were censored at the time of death or loss to follow-up. A new neurological deficit was defined as changes in global or focal neurological status attributable to the tumor and compared to the initial diagnosis for the observation group and before treatment in the SRS cohort. To control for potential confounders of treatment outcome, the two cohorts were matched, without replacement, in a 1:1 ratio using propensity scores derived from patients’ age, meningioma volume, tumor location, and duration of neuroimaging follow-up. Results The study analyzed both unmatched and matched patient and tumor attributes, as well as radiological and neurological outcomes for both cohorts. In the unmatched cohorts, there were 727 SRS patients and 388 conservatively managed patients. The SRS group had a mean age of 56.9 years, while the observation group had a mean age of 62.6 years. The mean initial Karnofsky Performance Status (KPS) was 90 in the SRS group and 100 in the observation group. The mean meningioma volume was 4.3 cc for the SRS group and 3.7 cc for the observation group. The mean radiologic follow-up durations for the SRS and conservatively managed cohorts were 57.2 and 43.5 months, respectively, while the mean clinical follow-up was 56.3 and 43.5 months, respectively. The mean dose to the tumor was 13.0 Gy in the SRS-treated cohort. After propensity score matching for patient age, duration of imaging follow-up, tumor location, and tumor volume, 311 patients remained in each cohort. The mean age was 61.1 years for the SRS cohort and 60.7 years for the conservatively managed cohort. The median KPS in the SRS and observation groups was 90 and 100, respectively. Mean tumor volumes were similar in both groups, and there were no appreciable differences in tumor side or midline location. In the unmatched cohorts, tumor control was observed in 99.0% of SRS-treated patients and 64.2% of observation cohort patients. Tumor progression-free survival favored SRS over the conservatively managed cohort. Tumor regression was observed in 45.4% of SRS-treated patients and 0.8% of patients in the observation cohort. No patients in the SRS cohort had evidence of radiation-associated intracranial malignancy. New neurological deficits attributable to meningioma were observed in 2.5% of SRS-treated and 2.8% of patients in the observation cohort. In the matched cohort analysis, tumor control was observed in 99.4% of the SRS cohort and 62.1% of the observation cohort, and tumor progression-free survival favored SRS over the conservatively managed cohort. Tumor regression was observed in 44.4% of the SRS cohort and 1% of the conservatively managed cohort. No patients in the SRS cohort had evidence of radiation-induced intracranial malignancy. New neurological deficits attributable to meningioma were observed in 2.3% of SRS-treated and 3.2% of observation cohort patients. Conclusion In conclusion, the study suggests that SRS is a superior treatment option for asymptomatic meningiomas compared to the observation method. SRS offers better radiological control and does not increase the risk of neurological deficits. Patients presenting with an asymptomatic meningioma and no immediate medical issues may benefit from SRS treatment. However, further research is needed to determine whether SRS treatment translates into the preservation or improvement of functional outcomes over a longer follow-up period. A randomized clinical trial of active surveillance vs SRS can help to further define the optimal management of asymptomatic meningiomas. Impact of the research This study contributes to the ongoing research on treatment options for asymptomatic low-grade meningiomas. These findings provide evidence for considering SRS as a treatment option for asymptomatic meningioma patients who are not imminently threatened by their condition. It also highlights the need for a randomized clinical trial of active surveillance versus SRS to reach an actionable conclusion in the optimal management of asymptomatic meningiomas.
My experience with ChatGPT.
Published on: May 10, 2023
As a PharmD student working part-time in Rhenix Lifesciences, content creation is a big part of my job. I spend my days learning about the mechanism of action of drugs and writing white papers, blogs, and short descriptions about diseases, as well as creating graphics that explain complex scientific concepts to a non-expert audience. Both of these areas of my life have been heavily impacted by ChatGPT. I've seen firsthand how ChatGPT can be a powerful tool for content creators, but I've also learned about its limitations and the importance of prompt engineering. In this blog post, I want to share my experience with ChatGPT and how it has impacted my studies and work as a content creator. I hope that by sharing my experience, I can help others who are interested in exploring generative AI, and also give them a better understanding of what ChatGPT can do and where it falls short. My first experience or interaction with ChatGPT My first interaction with ChatGPT happened on December 8, 2022, after watching a video that a friend shared with me. On signing up for the tool, I was pleasantly surprised to learn that it was free and easy to use.​ I decided to test it with a question that troubled me that day in the classroom. It was related to the different types of receptors present on the surface of B-cells. I was amazed at the level of detail with which it answered my question and its ability to recall the context of the discussion. How do I use it now? Since then, I've been using ChatGPT in various capacities, from learning about new concepts related to the pharmacology of drugs to generating engaging titles for my blog posts.​ When I encounter complex concepts during my studies, I turn to ChatGPT to simplify the explanation in layman's terms by copying and pasting the paragraph. Additionally, I utilize ChatGPT to create simplified tables from dense blocks of text found in pharmacology textbooks. It is also a helpful tool for creating multiple-choice questions (MCQs) and flashcards to aid in exam preparation and revision.​ For my work, I use it in the early literature research of a topic to broaden the outlines of my white paper. For example, while writing a clinical white paper on lung cancer, I asked ChatGPT to generate a list of all the types of bronchoscopies used in the diagnosis of tumors located in the lungs and respiratory system. After getting the list, I performed targeted searches on PubMed and read about them from peer-reviewed journal articles.​ I sometimes use ChatGPT to it improve the vocabulary of my text and rephrase it in a more suitable tone. For the blogs, it is good at suggesting some interesting titles if I provide the first paragraph of my blog post. Prompt engineering – the skill of asking questions After experimenting with ChatGPT, I quickly noticed that all of its responses were very generic and lacked creativity. This issue led me to discover the concept of prompt engineering, which involves the skill of asking precise questions to elicit specific responses from ChatGPT. For instance, if we ask ChatGPT to write an essay about visiting a zoo, the response will likely be bland and generic. However, if we ask ChatGPT to write about a visit to the zoo from the perspective of a child who believed pandas were mythical creatures, the response will be more unique and imaginative. We can even personalize ChatGPT's output by assigning it a persona, specifying the tone, and providing guidelines on what not to include in the response.​ I believe that prompt engineering will be central to producing the desired content from all the generative AI models and it will be the differentiating factor between good AI-generated content and bad AI-generated content. Professionals from all walks of life will have to learn how to effectively communicate with AI in order to stay competitive in their respective fields. Some limitations I found ChatGPT is a large language model trained by feeding the text created by humans, it inevitably reflects some of our cultural biases in its responses, which can be problematic. For example, if asked to write a story about a doctor, the model might assume the gender of the doctor to be male, and if asked to write about a nurse, it might assume the nurse to be female. Other similar biases have also been noted.​ Although OpenAI, the parent company of the model, has been working to eliminate these biases they are difficult to totally get rid of because they are inherent in the text data used to train the model. If removed by applying certain filters they may still show up in unexpected ways and scenarios.​ ChatGPT also makes up factual information and presents it in a very confident manner that can fool one into believing that it is correct. This phenomenon is called hallucination and it is a major drawback of text-based generative AI. As a large language model, it predicts the next word based on a series of previous words but that word may not be the most accurate one especially if it involves factual information. This limitation is particularly damaging in my field of writing where I am actively trying to equip my audience with medical information which can help them make well-informed decisions about their health. Therefore, I do not rely on ChatGPT to provide me with the content that I directly use or cite in the white papers or blogs. It is particularly bad at providing sources from the scientific literature. While it is not programmed to generate citations by default, when prompted to do so; it makes them up. It provides their links and when you click on them, they lead to error pages within the journal websites. It also struggles with arithmetic problems leading to some basic errors that can be surprising. Is it coming for our jobs? With its current abilities, generative AI including ChatGPT is pretty good at creating very decent-looking content. At the current level, it may not be able to outrightly replace human professionals but keep in mind that this is the first wave of generative AI. It has not had the time to mature and be a reliable tool and yet it has managed to send waves of concern around the creative industry. OpenAI and other tech companies have been working on such tools in the background but this recent publicity of ChatGPT and the associated funding as well as a sense of competition will spur further improvements and maturation of the technology as well as the introduction of new features.​ Despite this, AI cannot mimic the perspective of a human on a topic they are experts in. Moreover, it cannot solve unique problems. And given its unreliability and the tendency to produce uninspired content, hallucinate factual details and struggle in shockingly simple tasks, generative AI cannot replace human professionals in 2023. The only difference it will make is that humans effectively using AI will have a significant advantage over those who are not using it. AI has the potential to boost our productivity by reducing the time spent doing mundane tasks and providing us with more time to perform creative tasks. In a nutshell, I am using ChatGPT to save time on some of the mundane tasks as well as brainstorm some ideas at the beginning of a project. As a content creator, I am a little apprehensive about the rapidly evolving landscape of generative AI but overall, I am excited to use this disruptive technology to improve my productivity.
Exploring the safety and efficacy of a novel drug combination for treating recurrent high-grade astrocytomas: A phase 1 clinical trial.
Published on: February 01, 2023
Original author: Wu J, et al. (2021) (DOI: 10.1158/1078-0432.CCR-20-4730)
Astrocytoma is a type of brain tumor that originates from star-shaped glial cells in the brain called astrocytes. According to the WHO classification, they are classified into four grades based on the degree of malignancy and aggressiveness:​ 1. WHO Grade I or pilocytic astrocytoma 2. WHO Grade II or diffuse astrocytoma 3. WHO Grade III or anaplastic astrocytoma 4. WHO Grade IV or glioblastoma multiforme Pilocytic astrocytoma and diffuse astrocytoma are considered low-grade astrocytomas, while anaplastic astrocytoma and glioblastoma multiforme are considered high-grade astrocytomas. High-grade astrocytomas are difficult to treat due to their aggressive nature and resistance to therapy. These tumors often recur even after initial treatment, decreasing long-term survival rates. Current treatment options are often limited and may not effectively target the underlying biology of these tumors, leading to a need for more effective and targeted therapies. ​Zotiraciclib is an oral small-molecule inhibitor of cyclin-dependent kinases, specifically targeting CDK9. So far, the clinical investigations of its activity are mostly limited to hematological malignancies. Previously, the authors of the present study investigated the effects of zotiraciclib alone and in combination with temozolomide (TMZ) on glioma cell lines and animal models. They found that: ​Zotiraciclib penetrates the blood-brain barrier. 1. It suppresses transcription by inhibiting CDK9. 2. It decreases ATP by suppressing glycolysis and causing mitochondrial dysfunction, which leads to the selective killing of glioma cells. 3. It synergistically works with TMZ on both, TMZ-sensitive and resistant cells. 4. It increases the survival of the orthotopic glioblastoma mouse model. Based on these preclinical findings, they launched a phase 1 clinical trial looking into the safety and efficacy of zotiraciclib plus TMZ in recurrent glioblastoma and anaplastic astrocytoma patients (NCT02942264). Described below is a summary of the clinical trial. Methodology The primary objective was to determine the optimal dose and schedule by assessing safety through dose-limiting toxicity (DLT). Secondary endpoints included a progression-free survival rate at 4 months and patient-reported outcomes. The trial consisted of 2 phases; dose escalation and cohort expansion. Firstly, patients were randomly assigned to two arms, receiving either a dose-dense or metronomic TMZ schedule, in combination with zotiraciclib at different dose levels (150mg, 200mg, 250mg, 300mg). A Bayesian Optimal Interval design was used to establish the maximum tolerated dose (MTD). In the second phase, the trial was expanded in both arms and the patients were randomized to receive the MTD combination regimen until 18 patients have been treated at each dose. ​This clinical trial was conducted at the Center for Cancer Research of the National Cancer Institute (NCI), Bethesda, Maryland, USA. All the patients recruited were: ​1. Over 18 years old. 2. Had a histologically confirmed diagnosis of either anaplastic astrocytoma (intact 1p/19q chromosome) or glioblastoma/gliosarcoma. 3. Two or fewer prior relapses. 4. Not taking any drug that affects the inducers or inhibitors of CYP1A2 or 3A4. Patients in the dose-dense TMZ arm were given oral TMZ 125mg/m2 daily on days 1 to 7 and then 15 to 21. In the metronomic arm, it was given 50mg/m2 daily. Zotiraciclib was given 200mg per day orally on days 1, 12, 15, and 26 on a 28-day cycle, after a single initial dose given 3 days before cycle 1/day1. The BOIN design guided the dose escalation and de-escalation of zotiraciclib in each arm. After the MTD of zotiraciclib was determined, patients were randomized to receive zotiraciclib at the MTD combined with either dose-dense or metronomic TMZ. ​The trial assessed patients through physical examinations, toxicity evaluations, and laboratory investigations. Magnetic resonance imaging evaluation of the patient’s brain was completed at the baseline and every 2 cycles to determine the treatment response according to Response Assessment in Neuro-Oncology (RANO) Criteria. Toxicities were graded using the Common Terminology Criteria for Adverse Events (CTCAE Version 4.0) and the MD Anderson Symptom Inventory-Brain Tumor Module (MDASI-BT) was used to assess symptoms severity and interference in the patient's life. ​During the cohort expansion phase of the trial, patients participated in pharmacokinetics (PK), pharmacogenetics (PG), and neutrophil analysis. Blood samples were collected at various time points to measure complete blood count (CBC) with differential, blood smear, neutrophil chemotaxis, reactive oxygen species (ROS) production, and neutrophil cell surface markers. PK was characterized by measuring the plasma concentration of zotiraciclib using a liquid chromatography-tandem mass spectrometry assay and analyzing parameters such as the area under the curve (AUC), maximum plasma concentration (Cmax), and half-life T1/2. A baseline blood sample per patient was analyzed for the genotype of drug-metabolizing enzymes and transporters to compare patient exposures with different genotype groups. Results & discussion The study enrolled 53 patients between December 2016 and December 2019, 40 in the dose-escalation phase and 13 in the cohort expansion phase. The safety results showed that the DLT rate is proportional to the dosage of zotiraciclib in both arms. The non-hematologic DLTs included fatigue, elevated liver enzymes, and diarrhea, while neutropenia was the only hematologic DLT. Zotiraciclib-induced neutropenia was of special interest because it occurred after 24 hours of taking the drug and resolved within 72 hours. The most common non-hematologic adverse effects were alanine aminotransferase and aspartate aminotransferase elevation, diarrhea, fatigue, and nausea. ​In terms of primary and secondary outcomes: ​1. 250mg of zotiraciclib was established as the MTD in both arms. 2. PFS4 was 0.40 in Arm 1 (dose-dense TMZ) and 0.25 in Arm 2 (metronomic TMZ). Based on this, the dose-dense TMZ combined with 250mg zotiraciclib was selected as the optimal dose and schedule for future studies. Conclusion The combination of zotiraciclib and temozolomide showed promising results in terms of safety and tolerability. The study indicated that transient neutropenia is not severe enough to stop the further development of zotiraciclib. Further investigation with a larger sample size is needed to confirm these results. Impact of the research This study contributes to the ongoing research on treatment options for malignant astrocytomas, specifically glioblastoma, and anaplastic astrocytoma. The combination of zotiraciclib with temozolomide, a standard chemotherapy drug, shows promising results in terms of safety and tolerability. These findings pave the way for further investigations, including larger phase 2 and 3 clinical trials, to confirm the efficacy of this combination therapy and potentially improve outcomes for patients with recurrent high-grade astrocytomas.
Slowing down Alzheimer’s disease by combining an anti-oxidant drug, GV1001, with donepezil.
Published on: October 25, 2022
Original author: Koh, SH., Kwon, H.S., Choi, S.H., et al. (2021) (DOI: 10.1186/s13195-021-00803-w)
Alzheimer’s disease (AD) is a neurodegenerative disease that impairs short-term memory and affects the judgment and behavior of the patient. Brain cells continue to die as time passes and the patient eventually becomes dependent on round-the-clock care to perform basic tasks of everyday life such as bathing and changing clothes. In 2022, over 55 million people are living with dementia. Being the most common type of dementia, AD has become a global healthcare challenge of the 21st century. Currently, there is no disease-modifying treatment for AD. The symptoms are being managed using drugs such as donepezil, rivastigmine, and galantamine. These drugs have extensive side effects and do not stop the progression of AD. Efforts to develop an effective treatment for AD have failed to bear any fruit. One reason for disappointing results can be that most of the new drugs are targeting only the amyloid plaques – the extracellular deposits of the amyloid beta protein. Amyloid plaques are thought to play a central role in the disease's development and progression, but the pathophysiology of AD is multifaceted including inflammation and oxidative stress among other factors. Therefore, any effort to slow down or reverse AD should target inflammation and oxidative stress as well. The authors of this journal article conducted a phase 2 clinical trial to evaluate the safety and efficacy of a drug named GV1001. It is a 16-amino-acid peptide that corresponds to a portion of the human enzyme telomerase reverse transcriptase (TERT). GV1001 was originally developed as an anticancer drug but failed to show any efficacy in that regard. Later on, it was shown to have anti-inflammatory and antioxidant activity, as well as an ability to reduce the toxic effects of amyloid plaques which indicated its potential use in AD. Methodology It is a phase 2 clinical trial with a parallel design. The masking status was double-blind. A total of 109 participants were assessed for eligibility and 96 were enrolled in the trial. All 96 participants had probable AD as confirmed by the National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer’s Disease and Related Disorders Association criteria and the Diagnostic and Statistical Manual of Mental Disorders, 4th edition. Furthermore, the patients had a Korean Mini-Mental State Examination (K-MMSE) score of at least 19 at the screening visit and a Global Deterioration Scale (GDS) score of 5 to 6. The participants were also receiving stable doses of donepezil (10 mg) for more than 3 months before the screening visit. Magnetic resonance imaging (MRI) and computed tomography (CT) were performed to exclude patients who were suspected to have other types of dementia and psychotic conditions.​ The clinical trial included a screening visit, a double-blind treatment period of about 6 months, and an end-of-study visit. The participants were randomly assigned to receive a subcutaneous injection of 0.56 mg or 1.12 mg of GV1001 or a placebo every week for 4 weeks. This was followed by subcutaneous injections once every 2 weeks for 24 weeks. So, the overall injection count was 14 injections (4+10). The efficacy was evaluated at baseline, week 12, and week 24. Results & discussion The primary outcome was the difference in the Severe Impairment Battery (SIB) score of the participants between the start of the trial to week 24. Whereas, the secondary outcome was Clinical Interview-Based Impression of Change, Clinician Interview-Based Impression of Change plus caregiver input (CIBIC-plus), Clinical Dementia Rating Sum of Box (CDR-SOB), Alzheimer’s Disease Cooperative Study-Activities of Daily Living (ADCS-ADL), Neuropsychiatric Inventory (NPI), MMSE, and GDS scores. And finally, the safety of the drug was evaluated by considering adverse events (AEs), laboratory test results, vital signs, electrocardiogram findings, and physical examination.​ The SIB difference between the placebo group and GV1001 1.12 mg was 6.6 in the full set analysis (FAS) (p = 0.027) and 7.1 in the per-protocol set (PPS) (p = 0.018). This difference was lower between the placebo group and GV1001 0.56 mg. Among the secondary parameters, only NPI showed variation among the groups. It was found to be better in the group receiving GV1001 1.12 mg. The safety of GV1001 was found to be the same as the placebo.​ ​GV1001 protects neurons from the harmful effects of sustained inflammation. The above-mentioned results indicate that the antioxidant activity of GV1001 is beneficial to AD patients already receiving the standard donepezil therapy. GV1001 reduced the SIB decline at a dose of 1.12 mg in this phase 2 clinical trial. These results warrant a phase 3 clinical trial with a larger and more diverse sample. Impact of the research GV1001 provides another option to target the multifaceted pathophysiology of AD. It can potentially be combined with AD drugs to achieve better outcomes. This clinical trial provides evidence that GV1001 is safe and effective in slowing down AD. A phase 3 clinical trial is required to confirm this finding in a larger sample size.
Slowing down glioma growth by knocking out miR-21 in mice models.
Published on: August 05, 2022
Original author: L. Nieland et al. (2022) (DOI: 10.1016/j.omto.2022.04.001)
Glioblastoma multiforme (GBM) is an aggressive form of glioma with a median survival of 15 months. Heterogeneity is one of the main characteristics of GBM. The tumor cells show variability not only from one patient to another but within the same patient. Some of this heterogeneity occurs due to dysregulated microRNAs (miRNAs). miRNAs are non-coding RNA molecules that play a role in the expression of genes. In GBM, the most important miRNA is miR-21. A higher amount of miR-21 is linked to a worse prognosis.​ Studying the effect of the gain and loss of miR-21 on tumor growth in GBM can provide information about the role of miRNAs in these tumors. Previously, this has been tried using antisense oligonucleotide inhibitors. But these studies are limited due to the inherent shortcomings of antisense oligonucleotide inhibitors. The authors of this study set out to investigate the effects of miR-21 by knocking it out using clustered regulatory interspaced short palindromic repeats (CRISPR)-Cas technology. Methodology The researchers knocked out miR-21 in mouse (GL261 and CT2A) and human (U87) glioma lines using five different CRISPR RNAs (crRNAs). Eventually, JIR327 crRNA was selected because it showed more specificity according to DNA Sanger sequencing. CRISPR-Cas12a plasmids with co-expressing fluorescent markers allowed researchers to test the efficiency of editing and track the edited cells. Successfully, edited cells were isolated and cloned to obtain identical miR-21 knock-out (KO) cells. The expression of miR-21 and disrupted genomic sequences of these cell lines were tested using qRT-PCR and CRISPResso2, respectively. RNA sequencing (RNA-seq) was used to study the effect of the miR-21 level on the expression of other genes. Results & discussion The expression levels of miR-21 were significantly lower in GL261, CT2A, and U87 KO cell lines as compared to their wild-type (WT) counterparts. This decrease in miR-21 expression resulted in the upregulation of 25 genes and down-regulation of 27 genes. KO cell lines had significantly more expression of anti-proliferation genes such as cell division cycle 25 homolog A (Cdc25a), C-X-C motif chemokine ligand 10 (Cxcl10), Krev interaction trapped protein 1 (Krit1), signal transducer and activator of transcription 3 (Smad7), signal transducer and activator of transcription 3 (Stat3), and cyclin-dependent kinase 6 (Cdk6). More importantly, the researchers found that KO cell lines had reduced proliferation and migration, and smaller-sized colonies in vitro. When they injected KO and WT miR-21 into the striatum of separate mice groups, the KO groups showed increased survival compared to WT groups. Impact of the research This study paves the way for mRNA-based interventions in the field of cancer. By knocking out miR-21 from glioma cell lines, the authors of this study have shown that glioma growth is reduced. This reduction in growth can allow the currently available glioma interventions to be more effective.
