Current Molecular Pharmacology - Volume 16, Issue 8, 2023

Background: Despite the implementation of various cancer therapies, adequate therapeutic efficacy has not been achieved. A growing number of studies have been dedicated to the discovery of new molecules to combat refractory cancer cells efficiently. Recently, the use of a rare type of sugar, D-allose, has attracted the attention of research communities. In combination with the first-line treatment of cancers, including different types of radiotherapies and chemotherapies, D-allose has been detected with favorable complementary effects. Understanding the mechanism of therapeutic target molecules will enable us to develop new strategies for cancer patients that do not currently respond to the present therapies. Objective: We aimed to provide a review of the effects of D-allose in cancer treatment, its mechanisms of action, and gaps in this field that require more investigations. Discussion: With rare exceptions, in many cancer types, including head and neck, lung, liver, bladder, blood, and breast, D-allose consistently has exhibited anticancer activity in vitro and/or in vivo. Most of the D-allose functions are mediated through thioredoxin-interacting protein molecules. D-allose exerts its effects via reactive oxygen species regulation, cell cycle arrest, metabolic reprogramming, autophagy, apoptosis induction, and sensitizing tumors to radiotherapy and chemotherapy. Conclusion: D-allose has shown great promise for combating tumor cells with no side effects, especially in combination with first-line drugs; however, its potential for cancer therapy has not been comprehensively investigated in vitro or in vivo.

Type-2 diabetes mellitus is a prime factor for the development of Diabetic Nephropathy (DN) that affects the vital organ namely the kidneys, and further alters the functions of the nephron system. DN is nowadays becoming a challenge for scientists towards the world because of its high pervasiveness and complexity of medication. Various risk factors are involved in the initiation of pathogenic DN, which are associated with different pathways against drug activity. Due to this DN becomes an unpredictable query to the researchers. SIRT1 is a silent information regulator factor 2 related enzyme 1 (SIRT1) is nicotinamide adenine dinucleotide (NAD+) dependent deacetylase that functions as an intracellular regulator of transcriptional activity. An activated version of SIRT-1 improves the metabolic diseased conditions associated with other molecular pathways. SIRT1 attenuates diabetic nephropathy in in vitro and in vivo experimental models of diabetes containing Podocytes, Mesangial cells, and Renal proximal tubular cells. SIRT1 shows nephroprotective effects in DN in part through deacetylation of transcription factors i.e., imply in the disease like p53, PTP1B, FOXO, RelA, NF- kβ, STAT-3, and PGC-1α/ PPARγ. It has been shown that some natural products like resveratrol and synthetic compounds are activating the SIRT1, this further involved the cascade pathways to prevent the DN. This review will help regarding the effectiveness of SIRT1as target in the prevention and treatment of DN.

Cardiovascular disorders (CVDs) are the leading cause of death worldwide and are accelerated via the low level of low-density lipoprotein-cholesterol (LDL-C). The proprotein convertase subtilis/kexin type9 (PCSK9), a vital regulator and a biomarker, circulates for the LDL-C and has the degradation capability of the low-density lipoprotein receptor (LDLR). PCSK9 has modulated the overall mechanism by transcription, secretion, clearance, or extracellular inactivation in the past few years.PCSK9 has specific pathophysiological roles in many cardiovascular cells. The initial data on the PCSK9 inhibitor, Evolocumab, has a specific reduction in the composite end-point, such as cardiovascular, myocardial, and stroke, while the rest of the data release is still under wait. Furthermore, it is witnessed that the U.S. and the European authorities have approved two humanized antibodies against the LDL-R binding site of PCSK9. This review highlighted the recent data findings on the PCSK9 and its regulation, focusing on cardiovascular disorders, and summarized the current clinical studies. Thus it provides a ray of hope to overcome statin intolerance and alternative approaches for PSCK9 inhibition and significantly reduce cardiovascular complications. This review plays a pivotal role for the researchers and scientists working on PCSK9 inhibitors to treat cardiovascular disorders.

Cancers with a high capability for angiogenesis are frequently regarded as being difficult to treat. Anti-angiogenesis drugs are considered the primary therapy for these types of cancers. Due to intrinsic or acquired anti-angiogenesis resistance, therapies result in moderate clinical consequences, despite some hopeful findings. The importance of non-coding RNAs (ncRNAs) such as microRNAs (miRNAs), long non-coding (lncRNAs), and circular RNAs (circRNAs) in drug resistance mechanisms in cancer treatment has been discovered in the previous decade. Anti-angiogenic drug resistance can be influenced by ncRNA dysregulation. Hence, ncRNAs are potential drug resistance targets for new anti-angiogenic drugs in the inhibition of angiogenesis in tumors. Furthermore, some ncRNAs can be employed as biomarkers for anti-angiogenic drug responses and can be used to monitor cancer non-invasively. Combination treatment approaches, combined with routine anti-angiogenesis and some drugs that target the ncRNAs causing resistance, can be potential ways to overcome anti-angiogenesis resistance. For the first time, we explain the mechanisms of anti-angiogenic drug resistance and the related miRNAs and lncRNAs and their signaling pathways in commonly used antiangiogenic drugs implicated in this review article. These ncRNAs could be suggestions for targeting and reducing anti-angiogenic drugs in the future.

Background: Nasopharyngeal carcinoma (NPC) is a usual head and neck malignancy. Guggulsterone (GS) has potential in cancer chemoprophylaxis and treatment, but its therapeutic effect on NPC is unknown. We aimed to explore whether GS could promote the secretion of exosomal circFIP1L1 from NPC cells and its regulatory mechanism. Methods: NPC tissues and adjacent tissues were collected from NPC patients. Human nasopharyngeal epithelial cell lines (NP69) and NPC lines (5-8F, CNE1, and HNE1) were used for in vitro experiments. HNE1 cells were treated with GS (20, 40, 60 μmol/L). The expressions of miR-125a-5p and circFIP1L1 were evaluated by qRT-PCR. Cell proliferation and apoptosis abilities were measured by CCK-8 and flow cytometry. HNE1 cell exosomes were extracted and identified, and the levels of VEGFA and VEGFR2 were detected by ELISA. Then miR-125a-5p was knocked down and overexpressed. HUVECs angiogenesis was determined by the tube formation assay. qRT-PCR and Western blot were utilized to evaluate the expressions of VEGFA, MMP-2, MMP-9, and ICAM-1 in HUVECs. Results: miR-125a-5p was highly expressed in NPC tissues and cells. GS promoted the secretion of exosomal circFIP1L1 from HNE1 cells to affect HUVECs proliferation and angiogenesis. Overexpression of miR-125a-5p accelerated HUVECs proliferation and angiogenesis. Knocking down miR-125a- 5p inhibited VEGFA expression. In addition, exosomal circFIP1L1 sponged miR-125a-5p, inhibiting the VEGFA pathway to repress HUVECs angiogenesis. Conclusions: GS promoted exosomal circFIP1L1 in NPC cells to mediate miR-125a-5p/VEGFA axis affecting tumor angiogenesis.

Background: Melanoma, a highly malignant skin cancer, is a hot topic in oncology treatment research. Nowadays, tumor immunotherapy, especially immunotherapy combined with other therapies, has attracted more and more attention. Indoleamine 2,3-dioxygenase 2 (IDO2), a ratelimiting enzyme of the tryptophan metabolism pathway in the urine of dogs with immunosuppression, is highly expressed in melanoma tissue. Additionally, IDO2 significantly inhibits the anti-tumor immunity of the body and has become a novel target of melanoma treatment. Nifuroxazide, as an intestinal antibacterial agent, was found to be able to inhibit Stat3 expression and exert an anti-tumor effect. Therefore, the present study aimed to examine the therapeutic effect of a self-designed IDO2-small interfering RNA (siRNA) delivered by attenuated Salmonella combined with nifuroxazide on melanoma- bearing mice, as well as determine its underlying mechanism. Methods: The effect of nifuroxazide on melanoma was detected by flow cytometry, CCK-8 and colony- forming ability assays, respectively, in vitro. The plasmid of siRNA-IDO2 was constructed, and the mice-bearing melanoma model was established. After the treatment, the tumor growth and survival rate were monitored, and the morphological changes of tumor tissue were detected by HE staining. The expression of related proteins was detected by Western blotting, and the expression of CD4 and CD8 positive T cells in tumor tissue was detected by IHC and IF, and the proportion of CD4 and CD8 positive T cells in spleen was detected by flow cytometry. Results: The results demonstrated that the combination therapy effectively inhibited the phosphorylation of Stat3 and the expression level of IDO2 in melanoma cells, which effectively inhibited tumor growth and prolonged the survival time of tumor-bearing mice. The mechanistic study revealed that, compared with control groups and monotherapy groups, the combination treatment group reduced the atypia of tumor cells, increased the apoptotic rate, enhanced the infiltration of T lymphocytes in tumor tissue and increased the CD4⁺ and CD8⁺ T lymphocytes in the spleen, suggesting that the mechanism may be associated with the inhibition of tumor cell proliferation, the increase of apoptosis and the enhancement of the cellular immunity. Conclusion: In conclusion, IDO2-siRNA combined with nifuroxazide therapy could serve a significant role in the treatment of melanoma-bearing mice, enhance the tumor immunity and provide an experimental basis for identifying a novel combination method for the treatment of melanoma clinically.

Aims and Objective: This study aimed to unveil the specific function of lncRNA BBOX1 antisense RNA 1 (BBOX1-AS1) in ESCC cells and the underlying regulatory mechanism. Background: Esophageal squamous cell carcinoma (ESCC) is a deadly disease. Molecular mechanisms essential to ESCC development and progression require in-depth investigation. Long noncoding RNAs (lncRNAs) have been suggested as crucial effectors in modulating tumor growth. Methods: RT-qPCR and western blot examined the expression of genes and proteins of concern, respectively. Colony formation and EdU assays assessed the changes in cell proliferation. Sphere formation assay also detected the stemness of ESCC cells. Bioinformatics prediction, along with mechanistic assays (FISH, Subcellular fractionation, RNA pull-down, RIP, and luciferase reporter), was conducted to explore the gene interactions and regulatory relationship. Results: BBOX1-AS1 was observed to be aberrantly up-regulated in ESCC tissues and cell lines. BBOX1-AS1 depletion exerted suppressive impacts on ESCC cell proliferation and stemness, while BBOX1-AS1 overexpression led to the opposite consequences. Moreover, BBOX1-AS1 was verified to activate Hedgehog signaling pathway via up-regulating PTCH1, and BBOX1-AS1 could sponge miR-506-5p to up-regulate EIF5A, thus stabilizing PTCH1 mRNA. Rescue experiments indicated that BBOX1-AS1 could affect ESCC cell proliferation and stemness via modulation on PTCH1. Conclusion: To conclude, BBOX1-AS1 activates Hedgehog signaling pathway to facilitate the proliferation and stemness of ESCC cells via miR-506-5p/EIF5A/PTCH1 axis.

Objective: Diabetic nephropathy is an unavoidable complication of chronic uncontrolled diabetes mellitus. The pathogenesis of diabetic nephropathy is multifactorial, and the development of an effective therapy remains to be elucidated. The aim of the present study was to assess the role of NOX2 and Nrf2 in the protective mechanism of thymoquinone (THQ) against streptozotocin (STZ)-induced diabetic nephropathy. Methods: Rats were injected with STZ (55 mg/kg) to induce diabetes. The diabetic rats were orally treated with THQ (10 mg/kg/day) for eight weeks. Results: STZ-treated rats exhibit an elevation of serum creatinine, serum urea, and creatinine clearance. The renal abnormalities were associated with increased NADPH oxidase isoform, NOX2 protein expression, and activity, along with elevated malondialdehyde (MDA). In addition, the tumor necrotic factor-alpha (TNF-α) level and nitric oxide (NO) bioavailability, as well as the transforming growth factor-beta (TGF)-β, were markedly increased. On the other hand, the nuclear factor-E2-related factor (Nrf2) protein expression was significantly reduced in diabetic rats compared to the control. However, treatment with THQ significantly reversed these alterations with subsequent ameliorating renal dysfunction and pathological abnormalities. Conclusion: The present study demonstrates that THQ could protect against STZ-induced diabetic nephropathy by modulating the Nrf2/NOX2 signaling pathway.

Background: MicroRNAs (miRNA) are small non-coding RNAs that regulate the function of mRNA post-transcriptionally in a tissue-specific manner. miRNA expressions are heavily dysregulated in human cancer cells through various mechanisms, including epigenetic changes, karyotype abnormalities, and miRNA biogenesis defects. miRNAs may act as either oncogenes or tumor suppressors under different conditions. Epicatechin is a natural compound found in green tea which possesses antioxidant and antitumor properties. Objective: The objective of this study is to investigate the effect of epicatechin treatment on the expression level of several oncogenic and tumor suppressor miRNAs in breast and colorectal cancer cell lines (MCF7 and HT-29) and identify its mechanism of action. Methods: The MCF-7 and HT29 cells were treated with epicatechin for 24 hours and untreated cells were considered control cultures. miRNA was isolated and qRT-PCR was used to measure the expression profile changes of different oncogenic and tumor suppressor miRNAs. Furthermore, the mRNA expression profile was also screened at different concentrations of epicatechin. Results: Our results showed several-fold changes in miRNAs expression level, which is cell line specific. Also, epicatechin at different concentrations induces biphasic changes in mRNA expression levels in both cell lines. Conclusion: Our findings first time demonstrated that epicatechin can reverse the expression of these miRNAs and may trigger the cytostatic effect at a lower concentration.