Toward Early Diagnosis of Colorectal Cancer: Focus on Optical Nano Biosensors

BACKGROUND

Colorectal cancer is a leading cause of death among cancers worldwide, with the symptoms mimic other far more common lower gastrointestinal disorders.

OBJECTIVE

This challenge in separating colorectal cancer from other diseases has driven researchers to investigate a noninvasive screening technique and effective method. The early detection of colorectal cancer is imperative. Biomarkers play a critical role in colorectal screening tests, treatment, clinical and prognosis management. Therefore, sensitive and rapid biomarker detection would be helpful and demand the early diagnosis of colorectal cancer.

METHOD

Recently, several investigations have been performed to design biosensors for early detection of cancer diagnosis and profiling with strong applied ability and high sensitivity.

RESULT

In comparison, optical biosensors are one of the promising platforms for the cost-effective and rapid detection of biomarkers. This review will focus on the advancements and progress of the various optical-transducing approaches for diagnosing colorectal cancer.

CONCLUSION

Further, the prospects and limitations of these optical biosensors in colorectal cancer diagnosis will be discussed. Here, an overview of optical biosensors and meaningful information for scientists worldwide will be demonstrated.

The genetic factors contributing to the risk of cleft lip-cleft palate and their clinical utility

Cleft lip and cleft palate (CL/P) are among the most common congenital malformations in neonates and have syndromic or nonsyndromic forms. Nonsyndromic forms of malformation are being reported to be associated with chromosomal DNA modification by teratogenic exposure and to complex genetic contributions of multiple genes. Syndromic forms are shown to be related to chromosomal aberrations or monogenic diseases. There is a growing body of data illustrating the association of several genes with risk of developing this malformation, including genetic defects in T-box transcription factor-22 (TBX22), interferon regulatory factor-6 (IRF6), and poliovirus receptor-like-1 (PVRL1), responsible for X-linked cleft palate, cleft lip/palate-ectodermal dysplasia syndrome, and Van der Woude and popliteal pterygium syndromes, respectively. Genetic variants in MTR, PCYT1A, ASS1, SLC 25A13, GSTM1, GSTT1, SUMO1 BHMT1, and BHMT2 are being reported to be linked with CL/P risk. The etiology of nonsyndromic CLP is still remained to be unknown, although mutations in candidate genes have been found. Here, we provide an overview about the potential variants to be associated with CL/P for identification of the relative risk of CLP with respect to the basis of genetic background and environmental factors (e.g., dietary factors, alcohol use).

OXA-CuS@UiO-66-NH2 as a drug delivery system for Oxaliplatin to colorectal cancer cells

In this work, UiO-66-NH₂ was used to prepare a new delivery system by incorporating copper sulfide (CuS) into the pores. The CuS nanoparticles (NPs) were prepared to enhance the anticancer effects of Oxaliplatin (OXA) against colorectal cancer. The oxaliplatin was loaded into CuS@UiO-66-NH₂. To characterize and investigate their cytotoxicity effects, powder X-ray diffraction (PXRD), Fourier transformation infrared spectroscopy (FT-IR), Brunauer-Emmett-Teller (BET) analysis, UV-Visible analysis, inductively coupled plasma mass spectrometry (ICP-MS), and MTT assay were considered to be performed. According to the observations, the cytotoxicity of OXA-CuS@UiO-66-NH₂ was greater than that of the OXA alone.

Hydrogen-rich water exerts anti-tumor effects comparable to 5-fluorouracil in a colorectal cancer xenograft model

BACKGROUND

Colorectal cancer (CRC) is the third leading cause of cancer-related deaths in the world. Tumor removal remains the preferred frontline treatment; however, effective non-surgical interventions remain a high priority. 5-fluorouracil (5-FU) is a widely used chemotherapy agent, and molecular hydrogen (H₂) has been recognized for its antioxidant and anti-inflammatory effects, with research also suggesting its potential anti-tumor effects. Therefore, H₂ dissolved in water [hydrogen-rich water (HRW)], with or without 5-FU, may present itself as a novel therapeutic for CRC.

AIM

To investigate the effects of HRW, with or without 5-FU, as a novel therapeutic for CRC.

METHODS

CRC was induced in the left flank of inbred Balb/c mice. A total of 24 mice bearing tumors were randomly divided into four groups (n = 6 per group) and treated as follows: (1) Control group; (2) 5-FU group that received intraperitoneal injection of 5-FU (5 mg/kg) every other day; (3) H₂ group that received HRW, created and delivered via dissolving the H₂-generating tablet in the animals’ drinking water, with 200 μL also delivered by oral gavage; and (4) The combination group, H₂ (administered in same way as for group three) combined with 5-FU administered same way as group two.

RESULTS

Administration of HRW + 5-FU significantly improved tumor weight, tumor size, collagen content and fibrosis as compared to the CRC control group. Specifically, HRW attenuated oxidative stress (OS) and potentiated antioxidant activity (AA), whereas 5-FU treatment exacerbated OS and blunted AA. The combination of HRW + 5-FU significantly reduced tumor weight and size, as well as reduced collagen deposition and the degree of fibrosis, while further increasing OS and decreasing AA compared to administration of 5-FU alone.

CONCLUSION

Administration of HRW, with or without 5-FU, may serve as a therapeutic for treating CRC.

Emerging roles of CD133 in the treatment of gastric cancer, a novel stem cell biomarker and beyond

Gastric cancer (GC) is an aggressive disease with one of the highest mortality rates in the world. In the early stage, most patients are asymptomatic and early diagnosis is difficult. Recently, cancer stem cells (CSCs) have been highlighted as crucial emerging factors in the initiation or invasiveness of solid tumors. CD133, a CSC marker, is highly expressed in various tumors including gastric cancer. CD133-positive cells showed elevated malignant biological behaviors and CD133 upregulation is related to chemoresistance, cancer relapse, and poor prognosis. CD133 also plays an important role in the progression of tumors and metastasis. This review summarizes the current knowledge of the role of CD133 expression in GC and aims to contribute at identifying promising new strategies for treatment and management of gastric cancer.

The chance of COVID-19 infection after vaccination

The outbreak of COVID-19 that began in Wuhan, China, has constituted a new emerging epidemic that has spread around the world. There are some reports on illustrated the patients getting reinfected after recovering from COVID-19. Here we provide an overview of the biphasic cycle of COVID-19, genetic diversity, immune response and chance of reinfection after recovering from COVID-19. The new generation of COVID-19 is highly contagious and pathogenic infection can lead to acute respiratory distress syndrome. Whilst most patients suffer from a mild form of the disease, there is a rising concern that patients who recover from COVID-19 may be at risk of reinfection. The proportion of the infected population, is increasing worldwide; meanwhile, the rate and concern of reinfection by the recovered population are still high. Moreover, there are a few evidence on the chance of COVID-19 infection even after vaccination, which is around one per cent or less. Although the hypothesis of zero reinfections after vaccination has not been clinically proven, further studies should be performed on the recovered class in clusters to study the progression of the exposed with the re-exposed subpopulations to estimate the possibilities of reinfection and, thereby, advocate the use of these antibodies for vaccine creation.

Predominant monomorphism of the RIT2 and GPM6B exceptionally long GA blocks in human and enriched divergent alleles in the disease compartment

Across human protein-coding genes, the human neuron-specific genes, RIT2 and GPM6B, contain the two longest GA short tandem repeats (STRs) of 11 and 9-repeats, respectively, the length ranges of which are functional, and result in gene expression alteration. Here we sequenced the RIT2 and GPM6B STRs in 600 human subjects, consisting of late-onset neurocognitive disorder (n = 200), multiple sclerosis (n = 200), and controls (n = 200). Furthermore, we selected two large human databases, including the general-population-based gnomAD ( https://gnomad.broadinstitute.org ) and a mainly disease-phenotype-archiving database, TOPMed ( https://www.nhlbiwgs.org ), to compare allele frequencies in the general populations vs. the disease compartment. The RIT2 and GPM6B GA-repeats were monomorphic in the human subjects studied, at lengths of 11 and 9-repeats, respectively, and were predominantly human-specific in formula. Exception included a 9/11 genotype of the RIT2 GA-STR in an isolate case of female multiple sclerosis. Exceedingly rare alleles of the two GA repeats were significantly enriched in TOPMed vs. the gnomAD. We report prime instances of predominant monomorphism for specific lengths of STRs in human, and possible enrichment of rare divergent alleles in the disease phenotype compartment. While STRs are most attended because of their high polymorphic nature, STR monomorphism is an underappreciated feature, which may have a link with natural selection and disease.

Synthesis and characterization of amine-functionalized Fe3O4/Mesoporous Silica Nanoparticles (MSNs) as potential nanocarriers in drug delivery systems

Superparamagnetic Iron Oxide Nanoparticles (SPIONs) have shown great potential for being utilized in Nanocarriers (NCs) applications throughout the Drug Delivery System (DDS). However, there are several obstacles to make a practical magnetic NCs, such as low dispersity and high toxicity in the biological systems, and also low surface area for drug loading. In this work, magnetic NCs have been synthesized through a facile three-step process, first SPIONs were synthesized by the co-precipitation method, then decorated via mesoporous silica and finally the calcinated NCs functionalized with NH2 by a simple process in the ethanol solvent. The structure and morphology of the as-synthesized NCs have been characterized by the usage of different analyzing methods such as XRD, FTIR, TEM, FE-SEM, and TGA. Also, the magnetic properties have been investigated by the means of VSM throughout each step of the procedure. Lastly, we have applied the technique of N₂ adsorption-desorption to observe the surface area, pore size, and volume. Besides optimal magnetization of final nanoparticles (30 emu/gr), the as-synthesized NCs claimed the high surface area and small diameter, at 371 m².g^-1 and 70 nm, respectively. Moreover, the functionalized NCs have demonstrated well dispersity over a day in the PBS solution. As a result, the as-prepared nanocarrier able to overcome drug delivery obstacles and used as a potential nanocarrier owing to its small diameter, high surface area/ pore volume, optimal magnetization, and well dispersity in the biological condition.

Angiotensin-converting Enzyme Inhibitors and Angiotensin Receptor Blockers as Potential Therapeutic Options for Pancreatic Cancer

The renin-angiotensin system (RAS) has been reported to have a role in carcinogenesis, and therefore it may be of value as a potential therapeutic target in inhibiting tumor growth. It has been shown that inhibition of RAS via angiotensin I-converting enzyme inhibitors (ACEIs) and angiotensin II type-1 receptor (ARBs) inhibitors may have a protective effect against several malignancies. Here, we provide an overview of the potential value of the RAS pathway and targeting via ACE/ARB inhibitors in pancreatic cancer. Whilst the potential role of RAS as a target for the treatment of pancreatic cancer has been reported, the use of candesartan with gemcitabine failed to improve outcomes in pancreatic cancer. Another study of 1-3 years using ARB was found to reduce the risk of pancreatic cancer. In line with these trials, others have demonstrated that the ARBs in combination with gemcitabine might improve clinical outcomes in patients with advanced pancreatic cancer. Prospective trials are warranted to investigate this hypothesis.

Nigella sativa and its main constituent, thymoquinone protect against glycerol-induced acute kidney injury in rats

Objective

Rhabdomyolysis is a life-threatening disease caused by releasing myoglobin from injured myocytes, which results in acute kidney injury. In this study, the effect of aqueous-alcoholic extract of Nigella sativa (NS) and thymoquinone (TQ) on rhabdomyolysis-induced kidney damage in rats was investigated.

Materials and Methods

There were five groups of rats (n=8): Control, rhabdomyolysis, rhabdomyolysis treated with NS aqueous-alcoholic extract (200 and 400 mg/kg) and TQ (15 mg/kg). Treatments were given for 7 days (two days before and four days after glycerol injection). Glycerol was injected intramuscularly on the third day of the experiment for induction of rhabdomyolysis. Renal function parameters on the first, fourth, and seventh days of the experiment and renal oxidative stress and histological changes at the end of this study were assessed.

Results

Glycerol injection caused a significant increase in serum level of urea, creatinine, creatine phosphokinase, urine output and tissue MDA compared to the control animals (p<0.05-0.001). Administration of NS extract and TQ significantly decreased serum urea and creatinine on days 4 and 7, creatine phosphokinase on day 4, and urine output on day 7 compared to the rhabdomyolysis group (p<0.05-0.001). Compared to the rhabdomyolysis group, treatment with NS extract and TQ improved kidney histological abnormalities (p<0.01-0.001). The catalase enzyme activity in the group treated with NS 400 mg/kg and thiol content in the NS 400 mg/kg and TQ groups were significantly higher than those of the rhabdomyolysis group (p<0.05-0.01).

Conclusion

NS extract and to some extent TQ protect the kidney from rhabdomyolysis-induced injury.

An overview and bibliometric analysis on the colorectal cancer therapy by magnetic functionalized nanoparticles for the responsive and targeted drug delivery

With the growing demands for personalized medicine and medical devices, nanomedicine is a modern scientific field, and research continues to apply nanomaterials for therapeutic and damaged tissue diagnosis. In this regard, substantial progress has been made in synthesizing magnetic nanoparticles with desired sizes, chemical composition, morphologies, and surface chemistry. Among these materials, nanomagnetic iron oxides have demonstrated promise as unique drug delivery carriers due to cancer treatment. This carrier could lead to responsive properties to a specific trigger, including heat, pH, alternative magnetic field, or even enzymes, through functionalization and coating of magnetic nanoparticles, along with biocompatibility, good chemical stability, easy functionalization, simple processing, and ability to localize to the tumor site with the assistance of external magnetic field. Current studies have focused on magnetic nanoparticles' utilities in cancer therapy, especially for colorectal cancer. Additionally, a bibliometric investigation was performed on the public trends in the field of the magnetic nanoparticle to drug delivery and anticancer, which represented progressing applications of these carriers in the multidisciplinary zones with a general view on future research and identified potential opportunities and challenges. Furthermore, we outline the current challenges and forthcoming research perspective for high performance and fostering advanced MNPs in colorectal cancer treatment.

The Therapeutic Potential of MAPK/ERK Inhibitors in the Treatment of Colorectal Cancer

The MAPK/ERK signaling pathway regulates cancer cell proliferation, apoptosis, inflammation, angiogenesis, metastasis and drug resistance. Mutations and up-regulation of components of the MAPK/ERK signaling pathway, as well as over-activation of this critical signaling pathway, are frequently observed in colorectal carcinomas. Targeting the MAPK/ERK signaling pathway, using specific pharmacological inhibitors, elicits potent anti-tumor effects, supporting the therapeutic potential of these inhibitors in the treatment of CRC. Several drugs have recently been developed for the inhibition of the MEK/ERK pathway in preclinical and clinical settings, such as MEK162 and MK-2206. MEK1/2 inhibitors demonstrate promising efficacy and anticancer activity for the treatment of this malignancy. This review summarizes the current knowledge on the role of the MAPK/ERK signaling pathway in the pathogenesis of CRC and the potential clinical value of synthetic inhibitors of this pathway in preventing CRC progression for a better understanding, and hence, better management of colorectal cancer.

The Potential Therapeutic Value of Renin-Angiotensin System Inhibitors in the Treatment of Colorectal Cancer

Colorectal cancer is the third most common cancer globally. Despite extensive preclinical and clinical studies, it is still among the leading causes of cancer-related death, and a need for new therapeutic options is required. The renin-angiotensin system plays an important role in regulating blood pressure and cell growth. In addition to their hemodynamic effects, some of the renin-angiotensin system components, such as angiotensin, are also growth factors that promote cell proliferation and angiogenesis, and its dysregulation is reported to be associated with poor prognosis in colorectal cancer. Here we describe the critical role of the renin-angiotensin system pathway in colorectal cancer as well as the preclinical and clinical investigations renin-angiotensin system inhibitors: angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers as a potential therapeutic target in the treatment of colorectal cancer. Several studies have been shown that the inhibition of these pathways can reduce tumor growth and metastasis; however, some of the data remain inconsistent. There is accumulating evidence of the therapeutic potential of some inhibitors, such as Losartan which are now in clinical phases in the treatment of several malignancies using Nivolumab in combination with FOLFIRINOX in pancreatic cancer. Further investigations are warranted to improve the efficacy and selectivity of current and future anticancer strategies targeting renin-angiotensin systems.

Determination of flood probability and prioritization of sub-watersheds: A comparison of game theory to machine learning

Floods often significantly impact human lives, properties, and activities. Prioritizing areas in a region for mitigation based on flood probability is essential for reducing losses. In this study, two game theory (GT) algorithms - Borda and Condorcet - were used to determine the areas in the Tajan watershed, Iran that were most likely to flood, and two machine learning models - random forest (RF), and artificial neural network (ANN) - were used to model flood probability (the probability of flooding). Twelve independent variables (slope, aspect, elevation, topographic position index (TPI), topographic wetness index (TWI), terrain ruggedness index (TRI), land use, soil, lithology, rainfall, drainage density, and distance to river) and 263 locations of flooding were used to model and prepare flood-probability maps. The RF model was more accurate (AUC = 0.949) than the ANN model (AUC = 0.888). Frequency ratio (FR) was calculated for all factors to determine which had the most influence on flood probability. The values of twelve factors that affect flood probability were estimated for each sub-watershed. Then, game-theory algorithms were used to prioritize sub-watersheds in terms of flood probability. A pairwise comparison matrix revealed that the sub-watersheds most likely to flood. The Condorcet algorithm selected sub-watersheds 1, 2, 4, 5, and 11 and the Borda algorithm selected sub-watersheds 2, 4, 5, 20 and 11. Both models predicted that most of the watershed has very low flood probability and a very small portion has a high probability for flooding. The quantitative analysis and characterization of the watersheds from the perspective of flood hazard can support decision making, planning, and investment in mitigation measures.

When metal-organic framework mediated smart drug delivery meets gastrointestinal cancers

Cancers of the gastrointestinal tract constitute one of the most common cancer types worldwide and a ∼58% increase in the global number of cases has been estimated by IARC for the next twenty years. Recent advances in drug delivery technologies have attracted scientific interest for developing and utilizing efficient therapeutic systems. The present review focuses on the use of nanoscale MOFs (Nano-MOFs) as carriers for drug delivery and imaging purposes. In pursuit of significant improvements to current gastrointestinal cancer chemotherapy regimens, systems that allow multiple concomitant therapeutic options (polytherapy) and controlled release are highly desirable. In this sense, MOF-based nanotherapeutics represent a significant step towards achieving this goal. Here, the current state-of-the-art of interdisciplinary research and novel developments into MOF-based gastrointestinal cancer therapy are highlighted and reviewed.

The Therapeutic Potential of MEK1/2 Inhibitors in the Treatment of Gynecological Cancers: Rational Strategies and Recent Progress

The mitogen-activated protein kinase (MAPK) pathway is among the key factors in numerous cellular processes involved in tumorigenesis, suggesting it as a potential therapeutic target in gynecological cancer. MAPKs connect gene expression pathways and external stimulations. They include a network consisting of Ras, Raf or MAP3K, MEK or MAP2K, ERK or MAPK. Among these, MEK is an attractive molecular target of novel cancer therapeutics as it joints upstream activators and their corresponding downstream targets. MEK inhibitors were among the first inhibitors of the MAPK pathway entering into clinical trials. Several drugs have recently been developed as MEK inhibitors. MEK1/2 inhibitors demonstrate promising efficacy and anticancer activity to treat this malignancy and captured much attention in the past decade. Here, we summarize the role of MAPK/MEK/ERK pathway in the pathogenesis of gynecological cancer, with particular emphasis on MEK inhibitors in clinical settings, including PD-0325901, Selumetinib, Cobimetinib, Refametinib, Trametinib, Pimasertib, MEK162 and WX-554 in gynecologic cancers.

The Prognostic Value of Small Noncoding microRNA-21 Expression in the Survival of Cancer Patients: A Meta-Analysis

microRNA-21 (miR-21) is a small noncoding RNA that regulates gene expression in different types of human malignancies. The potential prognostic value of miR-21 in cancer progression is controversial. This meta-analysis includes 76 studies of 10,213 cancer patients to test miR-21 prognostic value in various human cancers. We obtain hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) for overall survival (OS) to assess association strength. In the pooled analysis, high miR-21 expression is associated with poor OS, with a combined HR of 1.59 (95% CI, 1.49-1.70; p < 0.001; random-effects model). Furthermore, subgroup analysis demonstrates that high miR-21 expression is related to shorter OS in patients with digestive system cancers (HR = 1.02; 95% CI, 1.002 to 1.04; p = 0.026), respiratory system cancers (HR = 1.93; 95% CI, 1.48 to 2.51; p < 0.001), and breast cancer (HR = 2.20; 95% CI, 1.78 to 2.73; p = 0.001). These results indicate that miR-21 may be a clinically useful prognostic biomarker for cancer progression.

Clinical Association between Phospho-AKT Expression with Clinicopathological Characteristics of Gastrointestinal Cancer Patients: A Meta-Analysis

Deregulation of AKT (protein kinase B) is frequently observed in human malignancies including gastrointestinal (GI) cancers. Here we have reviewed the association between AKT phosphorylation (activation) and clinical and pathological characteristics of patients with GI cancer. Articles in the EMBASE, PubMed, Cochrane Library, and Web of Science databases were searched up to July 2018. Eighteen studies comprising 1,698 patients with 5 different cancer types were included in the meta-analysis. In the pooled analysis, AKT phosphorylation was positively correlated with tumor size (r = 0.14, 95% CI: 0.06-0.22; P < 0.001), tumor grade (r = 0.08, 95% CI: 0.02-0.14; P < 0.009), tumor stage (r = 0.19, 95% CI: 0.13-0.24; P < 0.001), lymph node status (r = 0.18, 95% CI: 0.09-0.25; P < 0.001) and the presence of distant metastasis (r = 0.14, 95% CI: 0.06-0.22; P < 0.001) in the patients with GI cancer. These findings support the potential clinical value of AKT as a prognostic marker and therapeutic target in patients with GI carcinomas.

Metformin inhibits polyphosphate-induced hyper-permeability and inflammation

Circulating inflammatory factor inorganic polyphosphate (polyP) released from activated platelets could enhance factor XII and bradykinin resulted in increased capillary leakage and vascular permeability. PolyP induce inflammatory responses through mTOR pathway in endothelial cells, which is being reported in several diseases including atherosclerosis, thrombosis, sepsis, and cancer. Systems and molecular biology approaches were used to explore the regulatory role of the AMPK activator, metformin, on polyP-induced hyper-permeability in different organs in three different models of polyP-induced hyper-permeability including local, systemic short- and systemic long-term approaches in murine models. Our results showed that polyP disrupts endothelial barrier integrity in skin, liver, kidney, brain, heart, and lung in all three study models and metformin abrogates the disruptive effect of polyP. We also showed that activation of AMPK signaling pathway, regulation of oxidant/anti-oxidant balance, as well as decrease in inflammatory cell infiltration constitute a set of molecular mechanisms through which metformin elicits it's protective responses against polyP-induced hyper-permeability. These results support the clinical values of AMPK activators including the FDA-approved metformin in attenuating vascular damage in polyP-associated inflammatory diseases.

Therapeutic potential of active components of saffron in post-surgical adhesion band formation

BACKGROUND

Abdominal adhesions are common and often develop after abdominal surgery. There are currently no useful targeted pharmacotherapies for adhesive disease. Saffron and its active constituents, Crocin and Crocetin, are wildly used in traditional medicine for alleviating the severity of inflammatory or malignant disease.

PURPOSE

The aim of this study was to investigate the therapeutic potential of the pharmacological active component of saffron in attenuating the formation of post-operative adhesion bands using different administration methods in a murine model.

MATERIAL METHOD

saffron extract (100 mg/kg), Crocin (100 mg/kg), and Crocetin (100 mg/kg) were administered intraperitoneally and by gavage in various groups of male Wistar rat post-surgery. Also three groups were first treated intra-peritoneally by saffron extract, Crocin, and Crocetin (100 mg/kg) for 10 days and then had surgery. At the end of the experiments, animals sacrificed for biological assessment.

RESULT

A hydro-alcoholic extract of saffron and crocin but not crocetin potently reduced the adhesion band frequency in treatment and pre-treatment groups in the mice given intra-peritoneal (i.p) injections. Following the saffron or crocin administration, histological evaluation and quantitative analysis represented less inflammatory cell infiltration and less collagen composition, compared to control group. Moreover, the oxidative stress was significantly reduced in treatment groups.

CONCLUSION

These findings suggest that a hydro-alcoholic extract of saffron or its active compound, crocin, is a potentially novel therapeutic strategy for the prevention of adhesions formation and might be used as beneficial anti-inflammatory or anti-fibrosis agents in clinical trials.

TAXONOMY

Abdominal surgeries/post-surgical adhesions.

Rigosertib elicits potent anti-tumor responses in colorectal cancer by inhibiting Ras signaling pathway

BACKGROUND

The therapeutic potency of Rigosertib (RGS) in the treatment of the myelodysplastic syndrome has been investigated previously, but little is known about its mechanisms of action.

METHODS

The present study integrates systems and molecular biology approaches to investigate the mechanisms of the anti-tumor effects of RGS, either alone or in combination with 5-FU in cellular and animal models of colorectal cancer (CRC).

RESULTS

The effects of RGS were more pronounced in dedifferentiated CRC cell types, compared to cell types that were epithelial-like. RGS inhibited cell proliferation and cell cycle progression in a cell-type specific manner, and that was dependent on the presence of mutations in KRAS, or its down-stream effectors. RGS increased both early and late apoptosis, by regulating the expression of p53, BAX and MDM2 in tumor model. We also found that RGS induced cell senescence in tumor tissues by increasing ROS generation, and impairing oxidant/anti-oxidant balance. RGS also inhibited angiogenesis and metastatic behavior of CRC cells, by regulating the expression of CD31, E-cadherin, and matrix metalloproteinases-2 and 9.

CONCLUSION

Our findings support the therapeutic potential of this potent RAS signaling inhibitor either alone or in combination with standard regimens for the management of patients with CRC.

The Therapeutic Potential of Targeting the Angiotensin Pathway as a Novel Therapeutic Approach to Ameliorating Post-Surgical Adhesions

BACKGROUND

Post-surgical adhesion is a common complication after abdominal or pelvic surgeries. Despite improvements in surgical techniques or the application of physical barriers, little improvements have been achieved. It causes bowel obstruction, pelvic pain, and infertility in women and has an adverse effect on the quality of life. Renin-Angiotensin System (RAS) is traditionally considered as a blood pressure regulator. However, recent studies also indicate that the RAS plays a vital role in other processes, including oxidative stress, fibrosis, proliferation, inflammation, and the wound healing process. Angiotensin II (Ang II) is the main upstream effector of the RAS that can bind to the AT1 receptor (ATIR). A growing body of evidence has revealed that targeting Angiotensin-Converting Enzyme Inhibitors (ACEIs), Angiotensin II type 1 Receptor Blockers (ARBs), and Direct Renin Inhibitors (DRIs) can prevent post-surgical adhesions. Here we provide an overview of the therapeutic effect of RAS antagonists for adhesion.

METHODS

PubMed, EMBASE, and the Cochrane library were reviewed to identify potential agents targeting the RAS system as a potential approach for post-surgical adhesion.

RESULTS

Available evidence suggests the involvement of the RAS signaling pathway in inflammation, proliferation, and fibrosis pathways as well as in post-surgical adhesions. Several FDA-approved drugs are being used for targeting the RAS system. Some of them are being tested in different models to reduce fibrosis and improve adhesion after surgery, including Telmisartan, valsartan, and enalapril.

CONCLUSION

Identification of the pathological causes of post-surgical adhesion and the potential role of targeting Renin-Angiotensin System may help prevent this problem. Based on the pathological function of RAS signaling after surgeries, the administration of ARBs may be considered as a novel and efficient approach to prevent postsurgical adhesions. Pre-clinical and clinical studies should be carried out to have better information on the clinical significance of this therapy against post-surgical adhesion formation.