Efficient Induction of Apoptosis in Lung Cancer Cells Using Bismuth Sulfide Nanoparticles.

Background: The use of nanomaterial-based radiosensitizers to improve the therapeutic ratio has gained attraction in radiotherapy. Increased radiotoxicity applied to the tumor region may result in adverse impact on the unexposed normal cells to the radiation, a phenomenon known as radiation-induced bystander effect (RIBE). Objectives: This study aimed to investigate the effect of Bi2S3@BSA nanoparticles (NPs) as radiosensitizers on the enhancement of bystander response in non-irradiated cells. Materials and Methods: Lung carcinoma epithelial cells were exposed to 6 MV x-ray photons at different doses of 2 and 8 Gy, with and without Bi2S3@BSA NPs. The irradiated-cell's conditioned medium (ICCM) was collected and incubated with MCR-5 human fetal lung fibroblasts. Results: This study showed that ICCM collected from 2-Gy-irradiated A549 cells in the presence of Bi2S3@BSA NPs reduced the cell viability of MCR-5 bystander cells more than ICCM collected from irradiated cells without NPs (P<0.05), whereas such a difference was not observed after 8-Gy radiation. The mRNA expression of the BAX and XPA genes, as well as the cell death rate in MCR-5 bystander cells, revealed that the Bi2S3@BSA NPs significantly improved bystander response at 2-Gy (P<0.05), but the efficacy was not statistically significant after 8-Gy Irradiation. Conclusion: The results indicated that the presence of NPs did not affect bystander response enhancement at higher concentrations. These findings highlighted the potential use of radiation-enhancing agents and their benefits in radiotherapy techniques with high doses per fraction.

Translating mechanisms into therapeutic strategies for immune thrombocytopenia (ITP): Lessons from clinical trials.

Immune thrombocytopenia (ITP) is an autoimmune disorder that causes a significant reduction in peripheral blood platelet count. Fortunately, due to an increased understanding of ITP, there have been significant improvements in the diagnosis and treatment of these patients. Over the past decade, there have been a variety of proven therapeutic options available for ITP patients, including intravenous immunoglobulins (IVIG), Rituximab, corticosteroids, and thrombopoietin receptor agonists (TPO-RAs). Although the effectiveness of current therapies in treating more than two-thirds of patients, still some patients do not respond well to conventional therapies or fail to achieve long-term remission. Recently, a significant advancement has been made in identifying various mechanisms involved in the pathogenesis of ITP, leading to the development of novel treatments targeting these pathways. It seems that new agents that target plasma cells, Bruton tyrosine kinase, FcRn, platelet desialylation, splenic tyrosine kinase, and classical complement pathways are opening new ways to treat ITP. In this study, we reviewed the pathophysiology of ITP and summarized updates in this population's management and treatment options. We also took a closer look at the 315 ongoing trials to investigate their progress status and compare the effectiveness of interventions. May our comprehensive view of ongoing clinical trials serve as a guiding beacon, illuminating the path towards future trials of different drugs in the treatment of ITP patients.

Immune checkpoint inhibitors in gastrointestinal malignancies: an Umbrella review.

In the Modern era, immune checkpoint inhibitors (ICIs) have been the cornerstone of success in the treatment of several malignancies. Despite remarkable therapeutic advances, complex matrix together with significant molecular and immunological differences have led to conflicting outcomes of ICI therapy in gastrointestinal (GI) cancers. As far we are aware, to date, there has been no study to confirm the robustness of existing data, and this study is the first umbrella review to provide a more comprehensive picture about ICIs' efficacy and safety in GI malignancies. Systematic search on PubMed, Scopus, Web of Science, EMBASE, and Cochrane library identified 14 meta-analyses. The pooled analysis revealed that ICIs application, especially programmed death-1 (PD-1) inhibitors such as Camrelizumab and Sintilimab, could partially improve response rates in patients with GI cancers compared to conventional therapies. However, different GI cancer types did not experience the same efficacy; it seems that hepatocellular carcinoma (HCC) and esophageal cancer (EC) patients are likely better candidates for ICI therapy than GC and CRC patients. Furthermore, application of ICIs in a combined-modal strategy are perceived opportunity in GI cancers. We also assessed the correlation of PD-L1 expression as well as microsatellite status with the extent of the response to ICIs; overall, high expression of PD-L1 in GI cancers is associated with better response to ICIs, however, additional studies are required to precisely elaborate ICI responses with respect to microsatellite status in different GI tumors. Despite encouraging ICI efficacy in some GI cancers, a greater number of serious and fatal adverse events have been observed; further highlighting the fact that ICI therapy in GI cancers is not without cost, and further studies are required to utmost optimization of this approach in GI cancers.

Inhibitors of the PI3K/AKT/mTOR pathway in human malignancies; trend of current clinical trials.

The phosphoinositide 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) signaling pathway regulates proliferation, survival and metabolism, and its dysregulation is one of the most frequent oncogenic events across human malignancies. Over the last two decades, there has been significant focus on the clinical development of PI3K pathway inhibitors. More than 40 different inhibitors of this axis have reached various stages of clinical trials, but only a few of them have been approved by the Food and Drug Administration (FDA) for cancer treatment. These clinical results, however, could be improved given the importance of PI3K signaling in cancer and its role in linking cancer growth with metabolism. In this systematic review, after a glance at PI3K/AKT/mTOR pathway and its different inhibitors, we retrieved registered clinical trials evaluating the efficacy and safety of PI3K/AKT/mTOR inhibitors on Clinicaltrials.gov. Following the extraction of the data, finally we analyzed 2250 included studies in multiple steps, beginning with an overview and moving on to the details about type of malignancies, inhibitors, and treatment strategies. We also took a closer look at more than 100 phase III-IV clinical trials to pinpoint promising therapies, hoping that presenting a comprehensive picture of current clinical trials casts a flash of light on what remains to be done in future clinical trials of PI3K/AKT/mTOR inhibitors in human malignancies.

Synergistic effects of PI3K inhibition and pioglitazone against acute promyelocytic leukemia cells.

BACKGROUND: Although pioglitazone, a well-known anti-diabetic agent, has recently established itself as a pillar of cancer treatment, its therapeutic value could be attenuated by the aberrant activation of the PI3K/Akt pathway. AIM: To evaluate whether the PI3K/Akt suppression in leukemic cells could potentiate the anti-leukemic effects of pioglitazone. METHODS: To assess the anti-leukemic effects of PI3K/Akt inhibitors on anti-leukemic effects of pioglitazone, we used MTT and trypan blue assays. Flow cytometric analysis and qRT-PCR were also applied to evaluate cell cycle and apoptosis. RESULT: The resulting data revealed that upon PPARγ stimulation in different leukemic cell lines using pioglitazone, the survival and the proliferative capacity of the cells were significantly halted. Then, we evaluated the impact of the PI3K/Akt axis on the effectiveness of the drug in the most sensitive leukemic cell line; NB4 cells. Our results showed that treatment of NB4 cells with the PI3K inhibitors increased the sensitivity of leukemic cells to pioglitazone to the degree that even lower concentrations of the agent succeeded to induce apoptotic as well as the anti-proliferative effects. Moreover, it seems that PI3K inhibition could potentiate the anti-leukemic effect of pioglitazone through induction of p21-mediated sub-G1 cell cycle arrest and altering the balance between the pro-and anti-apoptotic genes. CONCLUSION: This study sheds light on the significance of the PI3K/Akt pathway in APL cell sensitivity to pioglitazone and proposed that the presence of the PI3K inhibitor in the therapeutic regimen containing pioglitazone could be promising in the treatment of this malignancy.

Host genetic diversity and genetic variations of SARS-CoV-2 in COVID-19 pathogenesis and the effectiveness of vaccination.

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), responsible for the outbreak of coronavirus disease 2019 (COVID-19), has shown a vast range of clinical manifestations from asymptomatic to life-threatening symptoms. To figure out the cause of this heterogeneity, studies demonstrated the trace of genetic diversities whether in the hosts or the virus itself. With this regard, this review provides a comprehensive overview of how host genetic such as those related to the entry of the virus, the immune-related genes, gender-related genes, disease-related genes, and also host epigenetic could influence the severity of COVID-19. Besides, the mutations in the genome of SARS-CoV-2 __leading to emerging of new variants__ per se affect the affinity of the virus to the host cells and enhance the immune escape capacity. The current review discusses these variants and also the latest data about vaccination effectiveness facing the most important variants.

Platelets in the perspective of COVID-19; pathophysiology of thrombocytopenia and its implication as prognostic and therapeutic opportunity.

Despite endorsed and exponential research to improve diagnostic and therapeutic strategies, efforts have not yet converted into a better prospect for patients infected with the novel coronavirus (2019nCoV), and still, the name of SARS-CoV-2 is coupled with numerous unanswered questions. One of these questions is concerning how this respiratory virus reduces the number of platelets (PLTs)? The results of laboratory examinations showed that about a quarter of COVID-19 cases experience thrombocytopenia, and more remarkably, about half of these patients succumb to the infection due to coagulopathy. These findings have positioned PLTs as a pillar in the management as well as stratifying COVID-19 patients; however, not all the physicians came into a consensus about the prognostic value of these cells. The current review aims to unravel the contributory role of PLTs s in COVID-19; and alsoto summarize the original data obtained from international research laboratories on the association between COVID-19 and PLT production, activation, and clearance. In addition, we provide a special focus on the prognostic value of PLTs and their related parameters in COVID-19. Questions on how SARS-CoV-2 induces thrombocytopenia are also responded to. The last section provides a general overview of the most recent PLT- or thrombocytopenia-related therapeutic approaches. In conclusion, since SARS-CoV-2 reduces the number of PLTs by eliciting different mechanisms, treatment of thrombocytopenia in COVID-19 patients is not as simple as it appears and serious cautions should be considered to deal with the problem through scrutiny awareness of the causal mechanisms.

The contributory role of lymphocyte subsets, pathophysiology of lymphopenia and its implication as prognostic and therapeutic opportunity in COVID-19.

The incidence of the novel coronavirus disease (COVID-19) outbreak caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has brought daunting complications for people as well as physicians around the world. An ever-increasing number of studies investigating the characteristics of the disease, day by day, is shedding light on a new feature of the virus with the hope that eventually these efforts lead to the proper treatment. SARS-CoV-2 activates antiviral immune responses, but in addition may overproduce pro-inflammatory cytokines, causing uncontrolled inflammatory responses in patients with severe COVID-19. This condition may lead to lymphopenia and lymphocyte dysfunction, which in turn, predispose patients to further infections, septic shock, and severe multiple organ dysfunction. Therefore, accurate knowledge in this issue is important to guide clinical management of the disease and the development of new therapeutic strategies in patients with COVID-19. In this review, we provide a piece of valuable information about the alteration of each subtype of lymphocytes and important prognostic factors associated with these cells. Moreover, through discussing the lymphopenia pathophysiology and debating some of the most recent lymphocyte- or lymphopenia-related treatment strategies in COVID-19 patients, we tried to brightening the foreseeable future for COVID-19 patients, especially those with severe disease.

Inhibition of PI3K signaling pathway enhances the chemosensitivity of APL cells to ATO: Proposing novel therapeutic potential for BKM120.

The latest molecular investigations leading to the discovery of the brand-new mechanisms associated to immortalized nature of cancer cells have questioned the efficacy of the conventional therapies and have increased the demand for more influential approaches, especially in the context of synergistic strategies. In an effort to enhance the effectiveness of acute promyelocytic leukemia (APL) treatment and to investigate the potential therapeutic value of Phosphoinositide 3-kinase (PI3K) inhibition synergism with chemotherapy, we designed experiments to evaluate the effect of Arsenic trioxide (ATO) in combination with BKM120 for the treatment of APL-derived NB4 cells. The results of the present study highlighted the favorable outcome of the PI3K inhibition using BKM120 in potentiating the anti-cancer effect of ATO, while reducing its cytotoxic concentration. Investigating the molecular mechanisms leading to this synergistic effect showed that probably down-regulation of the transcription factor SIRT1 coupled with suppression of c-Myc might halt the progression of the cell cycle from the G1 phase, resulting in the enhanced growth suppressive effect in ATO-plus-BKM120 combination. Moreover, we found that the positive regulatory role of the PI3K inhibition in augmenting the intracellular level of reactive oxygen species disturbed the balance between the death promoter and death repressor genes, which in turn amplified the caspase-3-dependent apoptotic activity of ATO in NB4. By and large, this study laid a therapeutic value on BKM120 in combination with ATO and suggested this combination as a novel therapeutic strategy that may be clinically accessible in the near future.

Novel pan PI3K inhibitor-induced apoptosis in APL cells correlates with suppression of telomerase: An emerging mechanism of action of BKM120.

The intertwining between cancer pathogenesis and perturbation of multitude signaling pathways ushered the cancer therapeutic approaches into an unbounded route of targeted therapies. For the nonce and among the plethora of promising inhibitors, intense interest has focused on small molecules targeting different component of PI3K axis. Intrigued by the constant activation of PI3K in leukemia, this study aimed to investigate the effects of BKM120, as the excelled member of pan PI3K inhibitors, in a panel of hematologic malignant cell lines. The resulting data showed that BKM120 exerted a concentration-dependent growth suppressive effect; however, IC50 values varied among the tested cells. Our results outlined that the blockage of PI3K in NB4, as the most sensitive cell line, resulted in a caspase-3-dependent apoptosis probably through NFκB-mediated suppression of c-Myc and hTERT. As far we are aware, to date, there have been no reports of BKM120 effect on enzymatic repression of telomerase, and this study represents for the first time that the anti-proliferative effect of the inhibitor on NB4 is mediated by down-regulation of telomerase; shedding new light on the novel mechanism of action of BKM120.

Inhibitor of pan class-I PI3K induces differentially apoptotic pathways in acute leukemia cells: Shedding new light on NVP-BKM120 mechanism of action.

Complex interplay of intracellular signaling networks, spanning from the extracellular environment to the nucleus, orchestrate normal cell growth and survival. Dysregulation of such signals contributes to malignant transformation, thereby giving the cancer cells a survival advantage, but also could be exploited for new anticancer interventions. The aim of this study was to investigate the effects of pan class-I PI3K inhibitor NVP-BKM120 on two distinct acute leukemia cell lines, NB4 (with mutant p53) and Nalm-6 (with wild-type p53). Our data highlighted the efficacy of the inhibitor against APL and pre B ALL cell lines; however, we failed to find an obvious correlation between p53 status and the sensitivity of leukemic cells to NVP-BKM120. Real-time PCR analysis revealed a significant up-regulation of p53 target genes in Nalm-6 cells, indicating a p53-dependent mechanism involved in NVP-BKM120 cytotoxicity. On the other hand, cytotoxic effects in mutant p53-expressing NB4 cells seem to be mediated mostly by the inhibition of the PI3K/Akt/NF-κB axis. In conclusion, we suggest NVP-BKM120 induces apoptosis through p53-dependent and -independent mechanisms, indicating the potential application of the inhibitor in both wild-type and deficient p53-expressing leukemic cells.