The Role of microRNAs in Hepatocellular Cancer: A Narrative Review Focused on Tumor Microenvironment and Drug Resistance.

Globally, hepatic cancer ranks fourth in terms of cancer-related mortality and is the sixth most frequent kind of cancer. Around 80% of liver cancers are hepatocellular carcinomas (HCC), which are the leading cause of cancer death. It is well known that HCC may develop resistance to the available chemotherapy treatments very fast. One of the biggest obstacles in providing cancer patients with appropriate care is drug resistance. According to reports, more than 90% of cancer-specific fatalities are caused by treatment resistance. By binding to the 3'-untranslated region of target messenger RNAs (mRNAs), microRNAs (miRNAs), a group of noncoding RNAs which are around 17 to 25 nucleotides long, regulate target gene expression. Moreover, they play role in the control of signaling pathways, cell proliferation, and cell death. As a result, miRNAs play an important role in the microenvironment of HCC by changing immune phenotypes, hypoxic conditions, and acidification, as well as angiogenesis and extracellular matrix components. Moreover, changes in miRNA levels in HCC can effectively resist cancer cells to chemotherapy by affecting various cellular processes such as autophagy, apoptosis, and membrane transporter activity. In the current work, we narratively reviewed the role of miRNAs in HCC, with a special focus on tumor microenvironment and drug resistance.

COVID-19 vaccines breakthrough infection and adverse reactions in medical students: a nationwide survey in Iran.

Introduction: There are different types of COVID-19 vaccines approved worldwide. Since no national studies focus on vaccine-related adverse reactions and breakthrough cases, this study aimed to investigate the rate of adverse events and COVID-19 infection in medical students in Iran. Methods: This retrospective cohort study included Iranian medical students who received two doses of COVID-19 vaccines. The medical team gathered the demographic characteristics, comorbidities, type of vaccine, adverse events following vaccination, and history of COVID-19 infection data through a phone interview. The frequency of adverse events and breakthrough infection was stratified by vaccine type (ChAdOx1-S, Gam-COVID-Vac, and BIBP-CorV). Results: A total of 3,591 medical students enrolled in this study, of which 57.02% were females, with a mean age of 23.31 + 4.87. A PCR-confirmed and suspicious-for-COVID-19 breakthrough infection rate of 4.51 and 7.02% was detected, respectively. There was no significant relation between breakthrough infection and gender, BMI, blood groups, and comorbidities. However, there was a significant difference in breakthrough infection rate among different types of vaccines (p = 0.001) and history of COVID-19 infection (p = 0.001). A total of 16 participants were hospitalized due to COVID-19 infection after vaccination for reasons such as dyspnea, abnormal imaging, or decreased oxygen saturation. No severe infection or death was observed in the studied population. Conclusion: Vaccination prevented severe COVID-19 infection, although a high breakthrough infection rate was evident among Iranian medical students during the Delta variant's peak. Vaccine effectiveness may be fragile during emerging new variants and in high-exposure settings. Moreover, adverse events are rare, and the benefits of vaccination outweigh the side effects. However, many limitations challenged this study, and the results should be cautious.

The effect of melatonin on capecitabine-induced hepatic and renal toxicity in rats.

BACKGROUND: Capecitabine (CAPE), an antimetabolite chemotherapy, can induce hepatic and renal toxicity. Melatonin (MEL), a neurohormone, possesses antioxidant, anti-apoptotic and anti-inflammatory effects. This study investigated the impact of MEL on capecitabine-induced hepatic and renal toxicity. METHODS AND MATERIALS: Twenty-five male Wistar rats were categorized into five groups for the study. The groups included a control group, MEL10 group (rats receiving daily intraperitoneal injections of 5 mg/kg MEL), CAPE 500 group (rats receiving weekly intraperitoneal injections of 500 mg/kg CAPE), CAPE + MEL five group, and CAPE + MEL 10 group. All groups were treated for a duration of 6 weeks. Various hematological, serological, biochemical, and histopathological assessments were conducted to evaluate the objective of the study. RESULTS: The administration of CAPE led to significant liver and kidney toxicity, as evidenced by elevated levels of malondialdehyde (MDA), myeloperoxidase (MPO), nitric oxide (NO), as well as serological markers including AST, ALT, ALP, BUN, and creatinine. CAPE exposure also resulted in a reduction in total antioxidant capacity (TAC) and glutathione peroxidase (GPx) levels. Histological examination revealed hyperemia in both liver and kidney tissues exposed to CAPE. However, treatment with MEL demonstrated positive effects. MEL administration alleviated oxidative stress, reduced levels of liver enzymes, BUN, and creatinine, and ameliorated histopathological degenerations. MEL also increased GPx and TAC levels. Moreover, MEL treatment aided in restoring the body weight that was lost due to CAPE exposure. CONCLUSION: Our findings indicated that the administration of MEL in rats significantly enhanced the hepatic and renal toxicity induced by CAPE.

Foreign body aspiration and mucormycosis: a case report.

Over the course of the Coronavirus disease 2019 (COVID-19) pandemic, numerous complications have been documented. In this report, we have detailed an unexpected complication of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection that occurred in a 73-year-old female patient who was simultaneously afflicted with mucormycosis and another unanticipated problem. Due to the lack of recovery of the patient after receiving mucormycosis treatment and continued fever, cough and hemoptysis, bronchoscopy was performed for her. During bronchoscopy, we encountered a foreign body that was the cause of the patient's fever, cough, and hemoptysis. Rigid bronchoscopy was performed and the foreign body was removed from the left main bronchus. The lack of a favorable treatment response after administering antifungal therapy suggested that the presence of a foreign body could potentially act as an underlying nidus, thus influencing the suboptimal therapeutic outcome. Mucormycosis is usually characterized by distinct radiological patterns. However, this case did not present predictable imaging findings, further complicating the diagnostic process associated with this invasive fungal infection.

The Role of microRNAs in Regulating Cancer Cell Response to Oxaliplatin-Containing Regimens.

Oxaliplatin (cyclohexane-1,2-diamine; oxalate; platinum [2+]) is a third-generation chemotherapeutic drug with anticancer effects. Oxaliplatin has a role in the treatment of several cancers. It is one of the few drugs which can eliminate the neoplastic cells of colorectal cancer. Also, it has an influential role in breast cancer, lung cancer, bladder cancer, prostate cancer, and gastric cancer. Although oxaliplatin has many beneficial effects in cancer treatment, resistance to this drug is in the way to cure neoplastic cells and reduce treatment efficacy. microRNAs are a subtype of small noncoding RNAs with ∼22 nucleotides that exist among species. They have diverse roles in physiological processes, including cellular proliferation and cell death. Moreover, miRNAs have essential roles in resistance to cancer treatment and can strengthen sensitivity to chemotherapeutic drugs and regimens. In colorectal cancer, the co-treatment of oxaliplatin with anti-miR-19a can partially reverse the oxaliplatin resistance through the upregulation of phosphatase and tensin homolog (PTEN). Moreover, by preventing the spread of gastric cancer cells and downregulating glypican-3 (GPC3), MiR-4510 may modify immunosuppressive signals in the tumor microenvironment. Treatment with oxaliplatin may develop into a specialized therapeutic drug for patients with miR-4510 inhibition and glypican-3-expressing gastric cancer. Eventually, miR-122 upregulation or Wnt/ß-catenin signaling suppression boosted the death of HCC cells and made them more sensitive to oxaliplatin. Herein, we have reviewed the role of microRNAs in regulating cancer cells' response to oxaliplatin, with particular attention to gastrointestinal cancers. We also discussed the role of these noncoding RNAs in the pathophysiology of oxaliplatin-induced neuropathic pain.

Toxic mechanisms of cadmium and exposure as a risk factor for oral and gastrointestinal carcinomas.

Incidence and mortality rates of gastrointestinal (GI) and oral cancers are among the highest in the world, compared to other cancers. GI cancers include esophageal, gastric, colon, rectal, liver, and pancreatic cancers, with colorectal cancer being the most common. Oral cancer, which is included in the head and neck cancers category, is one of the most important causes of death in India. Cadmium (Cd) is a toxic element affecting humans and the environment, which has both natural and anthropogenic sources. Generally, water, soil, air, and food supplies are reported as some sources of Cd. It accumulates in organs, particularly in the kidneys and liver. Exposure to cadmium is associated with different types of health risks such as kidney dysfunction, cardiovascular disease, reproductive dysfunction, diabetes, cerebral infarction, and neurotoxic effects (Parkinson's disease (PD) and Alzheimer's disease (AD)). Exposure to Cd is also associated with various cancers, including lung, kidney, liver, stomach, hematopoietic system, gynecologic and breast cancer. In the present study, we have provided and summarized the association of Cd exposure with oral and GI cancers.

miRNAs and Multiple Myeloma: Focus on the Pathogenesis, Prognosis, and Drug Resistance.

Multiple myeloma (MM) produces clonal plasma cells and aberrant monoclonal antibody accumulation in patients' bone marrow (BM). Around 1% of all cancers and 13% of hematological malignancies are caused by MM, making it one of the most common types of cancer. Diagnostic and therapeutic methods for managing MM are currently undergoing extensive research. MicroRNAs (miRNAs) are short noncoding RNAs that reduce or inhibit the translation of their target mRNA after transcription. Because miRNAs play an influential role in how myeloma develops, resources, and becomes resistant to drugs, miRNA signatures may be used to diagnose, do prognosis, and treat the myeloma response. Consequently, researchers have investigated the levels of miRNA in plasma cells from MM patients and developed tools to test whether they directly impacted tumor growth. This review discusses the latest discoveries in miRNA science and their role in the development of MM. We also emphasize the potential applications of miRNAs to diagnose, prognosticate, and treat MM in the future.

Pneumocystis jirovecii pneumonia complicated a case of SARS-CoV-2 infection and multiple sclerosis after treatment with rituximab.

Although immunodeficient patients are less prone to develop Coronavirus disease 2019 (COVID-19)-mediated cytokine storm, secondary infections can cause serious complications in this vulnerable population. They are more likely to develop opportunistic infections that can mimic the symptoms of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Herein, we presented a 27-year-old male patient of SARS-CoV-2 infection, who was complicated with Pneumocystis jirovecii pneumonia (PJP), following treatment with rituximab. First, he was hospitalized for 5 days with fever, cough, and dyspnea due to COVID-19 infection, and treated with remdesivir and glucocorticoid. Then, he has been referred to our center with cough, dyspnea, body pain, and fever. Due to persistent fever, the progression of pulmonary lesions, and reduced oxygen saturation, we began treatment with piperacillin + tazobactam, vancomycin, and levofloxacin. Nevertheless, the patient's fever did not stop after the aforementioned empiric treatment and his condition got worse and he was admitted to the intensive care unit. The result of BAL fluid, tested for P. jirovecii by RT-PCR, turned out to be positive. Therefore, we started trimethoprim-sulfamethoxazole and dexamethasone, which improved his condition. We hope this article helps clinicians consider causes other than COVID-19, especially opportunistic infections such as PJP, in patients with respiratory symptoms and fever.

Anticoagulant therapy in COVID-19: A narrative review.

Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), can manifest itself in several ways, including coagulopathy and thrombosis. These complications can be the first and sometimes only manifestations of SARS-CoV-2 infection and can occur early or late in the course of the disease. However, these symptoms are more prevalent in hospitalized patients with venous thromboembolism, particularly those admitted to intensive care units. Moreover, various forms of arterial and venous thrombosis, or micro- or macro-vasculature embolisms, have been reported during the current pandemic. They have led to harmful consequences, such as neurological and cardiac events, nearly all resulting from the hypercoagulable state caused by this viral infection. The severe hypercoagulability observed in patients with COVID-19 accounts for most cases of the disease that become critical. Therefore, anticoagulants seem to be one of the most vital therapeutics for treating this potentially life-threatening condition. In the current paper, we present a thorough review of the pathophysiology of COVID-19-induced hypercoagulable state and the use of anticoagulants to treat SARS-CoV-2 infections in different patient groups, as well as their pros and cons.

Interaction of quercetin and 5-fluorouracil: cellular and pharmacokinetic study.

5-fluorouracil (5-FU) is a widely used chemotherapeutic agent, and its uncontrolled blood levels contribute to toxicity. Quercetin, as an important flavonoid, has many biological effects, including anti-tumor and anti-inflammatory features. The current study investigated the synergistic effect between 5-FU and quercetin using HT-29 cell line and fibroblast cells. Rats were assigned to two groups. The 5-FU/quercetin group received intraperitoneal quercetin (10 mg/kg) and the Tween was injected to the control group for 14 consecutive days. On the 15th day, both groups received 50 mg/kg of 5-FU. Upon the final injection, blood samples were obtained at different times. Pharmacokinetic parameters were evaluated using high-performance liquid chromatography (HPLC). The mean (±SD) of maximum plasma concentration (Cmax) of 5-FU in combination therapy group was 3.10 ± 0.18 µg/ml and the area under the curve (AUC) was 153.89 ± 21.36, which increased by 113% and 128% compared to control group, respectively. Quercetin increased anti-tumor activity of 5-FU and enhanced Cmax and AUC of 5-FU. These findings confirm the synergistic effects between quercetin and 5-FU at the usual doses in cancer treatment, which may lead to reduced toxicity.

SARS-CoV-2 Omicron (B.1.1.529) Variant: A Challenge with COVID-19.

Since the beginning of the coronavirus disease 2019 (COVID-19) pandemic, there have been multiple peaks of the SARS-CoV-2 (severe acute respiratory syndrome coronavirus virus 2) infection, mainly due to the emergence of new variants, each with a new set of mutations in the viral genome, which have led to changes in the pathogenicity, transmissibility, and morbidity. The Omicron variant is the most recent variant of concern (VOC) to emerge and was recognized by the World Health Organization (WHO) on 26 November 2021. The Omicron lineage is phylogenetically distinct from earlier variants, including the previously dominant Delta SARS-CoV-2 variant. The reverse transcription-polymerase chain reaction (RT-PCR) test, rapid antigen assays, and chest computed tomography (CT) scans can help diagnose the Omicron variant. Furthermore, many agents are expected to have therapeutic benefits for those infected with the Omicron variant, including TriSb92, molnupiravir, nirmatrelvir, and their combination, corticosteroids, and interleukin-6 (IL-6) receptor blockers. Despite being milder than previous variants, the Omicron variant threatens many lives, particularly among the unvaccinated, due to its higher transmissibility, pathogenicity, and infectivity. Mounting evidence has reported the most common clinical manifestations of the Omicron variant to be fever, runny nose, sore throat, severe headache, and fatigue. This review summarizes the essential features of the Omicron variant, including its history, genome, transmissibility, clinical manifestations, diagnosis, management, and the effectiveness of existing vaccines against this VOC.

The role of cytokines and their antagonists in the treatment of COVID-19 patients.

The coronavirus disease 2019 (COVID-19) has various presentations, of which immune dysregulation or the so-called cytokine storm syndrome (COVID-CSS) is prominent. Even though cytokines are vital regulators of body immunoinflammatory responses, their exaggerated release can be harmful. This hyperinflammatory response is more commonly observed during severe COVID-19 infections, caused by the excessive release of pro-inflammatory cytokines, such as interleukin-1 (IL-1), IL-6, IL-8, tumour necrosis factor, granulocyte-macrophage colony-stimulating factor, and interferon-gamma, making their blockers and antagonists of great interest as therapeutic options in this condition. Thus, the pathophysiology of excessive cytokine secretion is outlined, and their most important blockers and antagonists are discussed, mainly focussing on tocilizumab, an interleukin-6 receptor blocker approved to treat severe COVID-19 infections.

Do we miss rare adverse events induced by COVID-19 vaccination?

Although severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has caused many complications, the invention of coronavirus disease 2019 (COVID-19) vaccines has also brought about several adverse events, from common side effects to unexpected and rare ones. Common vaccine-related adverse reactions manifest locally or systematically following any vaccine, including COVID-19 vaccines. Specific side effects, known as adverse events of particular interest (AESI), are unusual and need more evaluation. Here, we discuss some of the most critical rare adverse events of COVID-19 vaccines.