Inhibition of Helicobacter pylori growth and its cytotoxicity by 2-hydroxy 4-methoxy benzaldehyde of Decalepis hamiltonii (Wight & amp; Arn); a new functional attribute. Biochimie. 2011;93:678-688. [PMID: 21185348 DOI: 10.1016/j.biochi.2010.12.009]

Investigation of a novel Schiff base Catena-((μ6-(E)-2-((4-methoxy-2-oxidobenzylidene)ammonio)ethane-1-sulfonato potassium as a potential antibacterial agent

CONTEXT

Schiff bases, which have intriguing properties in many areas, have been studied extensively in recent years due to their structural properties and biological activities. In this research, a novel water-soluble Schiff base complex, Catena-((μ6-(E)-2-((4-methoxy-2-oxidobenzylidene) ammonio) ethane-1-sulfonato potassium, C10H14KNO6S (CMOAESP), was synthesized by a one-step condensation reaction of 2-hydroxy-4-methoxy benzaldehyde and taurine with the yield of 65%, 0.333 g. Spectral analysis of water-soluble crude product showed equilibria keto-enol tautomerism, by a resulting Zwitterionic form of the structure. The ADMET prediction showed that the CMOAESP obeys Lipinski's rule and was in bioavability range. The molecular docking results showed an inhibition ability for 1JIJ and MBT1 proteins which play an important role in antibacterial studies. The experimental end theoretical calculations were in a good agreement that CMOASP has inhibition efficiency against Escherichia coli and has inhibition at high concentrations against Staphylococcaceae aureus.

METHODS

The WinGX software system SHELXS direct technique was used to solve the structure, and SHELXL full-matrix least-squares approach on F2 was used to refine the results. The Gaussian 09W program was used to carry out the DFT calculations. The gap values for CMOAESP were calculated by using the B3LYP/6- 311 + + G(d,p) method in order to predict its reactivities and behaviors in the gas phase. The frontier orbitals, LUMO and HOMO together with some global parameters as electronegativity (μ), chemical potential (χ), hardness (η), electrophilicity index (ω), and softness (S) values were predicted from DFT calculations.

Characterization of Four Piper Essential Oils (GC/MS and ATR-IR) Coupled to Chemometrics and Their anti-Helicobacter pylori Activity

Background: Essential oils represent a major class of natural products which are known for their antimicrobial activity. This study aimed to determine the composition of four Piper essential oils by gas chromatography mass spectrometry, attenuated total reflection infrared, and chemometric analysis. Results: Monoterpene was the most predominant class in Piper nigrum and white pepper (87.6 and 80%, respectively) with the dominance of α-pinene, β-pinene, 3-carene, limonene, and β-caryophyllene. Sesquiterpenes represented 50, 19.6, and 12.3% of the essential oils of Piper longum, white pepper, and P. nigrum, respectively. Unlike other species, Piper cubeba oil was found to be rich in aromatics (59%), with eugenol (10.7%) and methyl eugenol (47.4%) representing the major components along with β-myrcene (21.2%) and 1,8-cineole (6.4%). Only P. longum essential oil comprised about 18.2% of alkanes and 13.6% of alkenes. Application of chemometric analysis utilizing GC/MS and ATR-IR data displayed the same segregation pattern where both principal component analysis and hierarchal cluster analysis revealed that white pepper was most closely related to P. nigrum while being completely discriminated from other Piper species. The Piper oils showed promising inhibitory effects on Helicobacter pylori. P. longum oil recorded the most efficient anti-Helicobacter activity [minimum inhibitory concentration (MIC) value of 1.95 μg/ml, which is the same as the MIC of clarithromycin], followed by the oil of white pepper (MIC = 3.90 μg/ml), while P. cubeba and P. nigrum produced the lowest activity (MIC value of 7.81 μg/ml). Conclusion: Piper essential oils can be used as nutritional supplements or therapeutic drugs to protect against H. pylori infection.

Phytochemical discrimination of Pinus species based on GC-MS and ATR-IR analyses and their impact on Helicobacter pylori

INTRODUCTION

The leaves and cones of Pinus plants as well as their essential oils have been used in traditional medicine for the treatment of several ailments.

OBJECTIVES

Phytochemical discrimination of Pinus species and investigation of their anti-Helicobacter pylori activity in vitro and in silico.

MATERIALS AND METHODS

Gas chromatography-mass spectrometry (GC-MS) and attenuated total reflectance infrared (ATR-IR) metabolic profiling of the essential oils of Pinus species. Principal component analysis (PCA) and hierarchal cluster analysis (HCA) were applied for discrimination and segregation of Pinus species.

RESULTS

GC-MS revealed the presence of 76 constituents, where monoterpenes represented the major class with the dominance of α-pinene (72%) followed by β-pinene (16%) for P. canariensis. β-Pinene was the dominant component in P. pinea (24%) followed by terpinolene (11%). α-Pinene (17%) and caryophyllene (12%) were the major components in P. halepensis, while, 3-carene (33%) and α-pinene (17%) represented the major constituents of P. roxburghii oil. By applying PCA and HCA on GC-MS and ATR-IR data analysis, ATR-IR displayed much better discrimination for Pinus species. The pine oils showed promising inhibitory effects on Helicobacter pylori. Furthermore, in silico molecular modelling was carried out where the calculated free binding energies of phytochemicals identified ranged from -33.71 to -19.67 kcal/mol for urease and -41.18 to -16.57 kcal/mol for shikimate kinase. This suggests favourable binding of pine essential oil components to both enzymes, thus explaining their potential inhibitory activity on H. pylori.

CONCLUSION

GC-MS and ATR-IR based metabolic analyses could discriminate between Pinus species. Pine essential oils can be used as promising therapeutic drugs to protect against H. pylori infection.

Emerging role of microbiota in immunomodulation and cancer immunotherapy

Gut microbiota is emerging as a key modulator of the immune system. Alteration of gut microbiota impacts functioning of the immune system and pathophysiology of several diseases, including cancer. Growing evidence indicates that gut microbiota is not only involved in carcinogenesis but also has an impact on the efficacy and toxicity of cancer therapy. Recently, several pre-clinical and clinical studies across diverse cancer types reported the influence of gut microbiota on the host immune response to immunotherapy. Advancement in our understanding of the mechanism behind microbiota-mediated modulation of immune response is paramount for their utilization as cancer therapeutics. These microbial therapies in combination with conventional immunotherapeutic methods have the potential to transform the pre-existing treatment strategies to personalized cancer therapy. In this review, we have summarized the current status of research in the field and discussed the role of microbiota as an immune system modulator in context of cancer and their impact on immunotherapy.

2-Hydroxy-4-methoxybenzaldehyde from Hemidesmus indicus is antagonistic to Staphylococcus epidermidis biofilm formation

Staphylococcus epidermidis (SE) is an opportunistic nosocomial pathogen that accounts for recalcitrant device-related infections worldwide. Owing to the growing interest in plants and their secondary metabolites targeting bacterial adhesion, this study was intended to uncover the anti-biofilm potential of Hemidesmus indicus and its major constituent 2-hydroxy-4-methoxybenzaldehyde (HMB) against SE. The minimum biofilm inhibitory concentration (MBIC) of H. indicus root extract and HMB were found to be 500 and 250 µg ml^-1, respectively. The results of time-dependent biofilm inhibition and mature biofilm disruption assays confirmed that HMB targets initial cell adhesion. Furthermore, interference by HMB in the expression of adhesin genes (icaA, aap and bhp) and biofilm components was associated with an increased susceptibility of SE to oxidative stress and antibiotics. To conclude, this study reports for the first time HMB as a potential drug against SE biofilms.

Gastroprotective effects of Erythrina speciosa (Fabaceae) leaves cultivated in Egypt against ethanol-induced gastric ulcer in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Members of the genus Erythrina have been traditionally used in the treatment of various ailments such as inflammation and gastrointestinal disorders. Erythrina speciosa (Fabaceae) is a spiny, deciduous shrub or small tree native to Southern America in Brazil. It is cultivated in Africa and Asia. The traditional usage of E. speciosa indicated its antibacterial, analgesic, and anti-inflammatory activities.

AIM OF THE STUDY

Evaluation of the phytochemical constituents, gastroprotective effects and possible mechanism of action of the ethyl acetate fraction obtained from the methanol extract of E. speciosa leaves (ESLE).

MATERIALS AND METHODS

Chemical characterization of ESLE was done using high performance liquid chromatography coupled to mass spectrometry (HPLC-MS). The gastroprotective activity of ESLE was evaluated using ethanol-induced gastric-ulcer model in rats. Rats were pre-treated with ESLE 25, 50 and 100 mg/kg 1 h before the administration of absolute ethanol. Histological analysis, mucin content, and total acidity were evaluated. The possible mechanism of action of ESLE was studied through the examination of oxidative stress and inflammatory markers, PGE2, and NF-κB, iNOS, COX-2, and HSP-70 immunoexpression. In vitro, anti-Helicobacter pylori activity of ESLE was also studied using micro-well dilution method.

RESULTS

Fourteen compounds were tentatively identified including alkaloids, flavonoids, and saponins. ESLE exerted a powerful gastroprotective effect. The pre-treatment with ESLE at different doses resulted in a significant reduction in gastric lesions and significant elevation in the mucin production. These effects could be partially mediated by the potent anti-inflammatory activity of ESLE as evidenced by the significant reduction in the immunoexpression of NF-κB, COX-2, iNOS and the reduction in the pro-inflammatory marker, TNF-α. ESLE counteracted the ethanol-induced oxidative stress by increasing the levels of depleted GSH and catalase as well as significantly attenuating the ethanol-induced lipid peroxidation tissue levels. In addition, ESLE exhibited in vitro antibacterial activity against H. pylori.

CONCLUSIONS

The chemical constituents of ESLE strongly support its potent gastroprotective effect suggesting its future potential application in the management of gastric ulcer by eliminating its symptoms and causes including H. pylori.

Explication of the Potential of 2-Hydroxy-4-Methoxybenzaldehyde in Hampering Uropathogenic Proteus mirabilis Crystalline Biofilm and Virulence

Proteus mirabilis is an important etiological agent of catheter-associated urinary tract infections (CAUTIs) owing to its efficient crystalline biofilm formation and virulence enzyme production. Hence, the present study explicated the antibiofilm and antivirulence efficacies of 2-hydroxy-4-methoxybenzaldehyde (HMB) against P. mirabilis in a non-bactericidal manner. HMB showed concentration-dependent biofilm inhibition, which was also evinced in light, confocal, and scanning electron microscopic (SEM) analyses. The other virulence factors such as urease, hemolysin, siderophores, and extracellular polymeric substances production as well as swimming and swarming motility were also inhibited by HMB treatment. Further, HMB treatment effectively reduced the struvite/apatite production as well as crystalline biofilm formation by P. mirabilis. Furthermore, the results of gene expression analysis unveiled the ability of HMB to impair the expression level of virulence genes such as flhB, flhD, rsbA, speA, ureR, hpmA, and hpmB, which was found to be in correlation with the results of in vitro bioassays. Additionally, the cytotoxicity analysis divulged the innocuous characteristic of HMB against human embryonic kidney cells. Thus, the present study reports the potency of HMB to act as a promising therapeutic remedy for P. mirabilis-instigated CAUTIs.

Microwave-assisted Single Step Cinnamic Acid Derivatization and Evaluation for Cytotoxic Potential

BACKGROUND

Phenylpropylene biosynthesis pathway plays a crucial role in the vanillin and their derivative(s) production in the plants. The intermediate of vanillin synthesis i.e. cinnamic acid (CA) is converted into 2-Hydroxy 4-MethoxyBenzaldehyde (HMB) in Decalepis arayalpathra having a number of therapeutic value.

OBJECTIVE

Microwave-assisted modifications in cinnamic acid were planned for potential anticancer properties with better yield and efficiency. The present study also confirms the presence of HMB and its precursor i.e. cinnamic acid in D. arayalpathra tubers.

METHODS

We used a single step Microwave Assisted Synthesis (MAS) to modify cinnamic acid, and then examined the synthetic and natural cinnamic acid derivatives anticancer potential against six human cancer (K-562, WRL-68, A549, A431, MCF-7, and COLO-201) and two normal (L-132 and HEK-293) cell lines at 2, 10 and 50 µg/ml concentrations.

RESULTS

β-bromostyrene and β -nitrostyrene have shown inhibition with IC50 values ranging 0.10-21 µM and 0.03-0.06 µM, respectively to the cancer cell lines. β-bromostyrene was the most potent anticancer derivative of CA with better cellular safety and biocompatibility.

CONCLUSION

The present study of microwave-assisted synthesis demonstrates a single-step modification in cinnamic acid. MAS is a fast, reliable, and robust method. The resultant compounds have shown in-vitro anticancer activity against human lung carcinoma and breast adenocarcinoma.

Amruthapala (Decalepis arayalpathra (J. Joseph and V. Chandras.) Venter): A Comprehensive Review on Diversity, Therapeutic Uses, and Valorization of Bioactive Constituents

BACKGROUND

Decalepis arayalpathra (J. Joseph and V. Chandras.) Venter is used primarily for nutrition besides its therapeutic values. Traditional preparations/formulations from its tuber are used as a vitalizer and blood purifier drink. The folklore medicinal uses cover inflammation, cough, wound healing, antipyretic, and digestive system management. A comprehensive review of the current understanding of the plant is required due to emerging concerns over its safety and efficacy.

OBJECTIVE

The systematic collection of the authentic information from different sources with the critical discussion is summarised in order to address various issues related to botanical identity, therapeutic medicine, nutritional usage, phytochemical, and pharmacological potentials of the D. arayalpathra. Current use of traditional systems of medicine can be used to expand future research opportunities.

MATERIALS AND METHODS

Available scripted information was collected manually, from peered review research papers and international databases viz. Science Direct, Google Scholar, SciFinder, Scopus, etc. The unpublished resources which were not available in database were collected through the classical books of 'Ayurveda' and 'Siddha' published in regional languages. The information from books, Ph.D. and MSc dissertations, conference papers and government reports were also collected. We thoroughly screened the scripted information of classical books, titles, abstracts, reports, and full-texts of the journals to establish the reliability of the content.

RESULTS

Tuber bearing vanilla like signature flavor is due to the presence of 2-hydroxy-4-methoxybenzaldehyde (HMB). Among five other species, Decalepis arayalpathra (DA) has come under the 'critically endangered' category, due to over-exploitation for traditional, therapeutic and cool drink use. The experimental studies proved that it possesses gastro-protective, anti-tumor, and antiinflammatory activities. Some efforts were also made to develop better therapeutics by logical modifications in 2-Hydroxy-4-methoxy-benzaldehyde, which is a major secondary metabolite of D. arayalpathra. 'Amruthapala' offers the enormous opportunity to develop herbal drink with health benefits like gastro-protective, anti-oxidant and anti-inflammatory actions.

CONCLUSION

The plant has the potential to generate the investigational new lead (IND) based on its major secondary metabolite i.e. 2-Hydroxy-4-methoxy-benzaldehyde. The present mini-review summarizes the current knowledge on Decalepis arayalpathra, covering its phytochemical diversity, biological potentials, strategies for its conservation, and intellectual property rights (IPR) status. Chemical Compounds: 2-hydroxy-4-methoxybenzaldehyde (Pubchem CID: 69600), α-amyrin acetate (Pubchem CID: 293754), Magnificol (Pubchem CID: 44575983), β-sitosterol (Pubchem CID: 222284), 3-hydroxy-p-anisaldehyde (Pubchem CID: 12127), Naringenin (Pubchem CID: 932), Kaempferol (Pubchem CID: 5280863), Aromadendrin (Pubchem CID: 122850), 3-methoxy-1,2-cyclopentanedione (Pubchem CID: 61209), p-anisaldehyde (Pubchem CID: 31244), Menthyl acetate (Pubchem CID: 27867), Benzaldehyde (Pubchem CID: 240), p-cymene (Pubchem CID: 7463), Salicylaldehyde (Pubchem CID: 6998), 10-epi-γ-eudesmol (Pubchem CID: 6430754), α -amyrin (Pubchem CID: 225688), 3-hydroxy-4-methoxy benzaldehyde (Pubchem CID: 12127).

Phyto anti-biofilm elicitors as potential inhibitors of Helicobacter pylori

Helicobacter pylori (H. pylori) infection is a global public health concern. Due to its high adaptability in various adverse environments (temperature, pH, adhesion, phenotypic forms), targeting the bacterium is quite challenging. Moreover, due to its high persistence, decreased patience compliance and emerging antibiotic resistance, researchers have been forced to search for novel candidates with lesser or no side effects. Hence, in the current study, phytobioactives have been screened for its anti-biofilm attributes against H.pylori. Gastric biopsy samples have been screened using confirmatory techniques (microbiological, biochemical and molecular) for their virulent and non-virulent biomarkers. Physico-nutritive parameters were standardized. H. pylori biofilms were assessed using microtitre plate assay. Biofilms' biomass and exopolysaccharide have been evaluated using crystal violet and ruthenium red staining, respectively. Anti-biofilm screening was performed using potent aqueous phytochemicals namely Acorus calamus, Colocasia esculenta and Vitex trifolia. The results indicated the confluent growth of the H. pylori biofilms confirmed through genotyping and grew best at 37 °C for 72 h at a pH of 7.5 on polystyrene plates. Further, among the phytochemicals tested, Acorus calamus exhibited the highest H. pylori anti-biofilm activity via a dose-dependent pattern. The overall observations of the study will pave way for newer approaches to understand and combat bacterial pathogenesis and will contribute towards better health and hygiene.

Neuroprotective effect of Decalepis hamiltonii aqueous root extract and purified 2-hydroxy-4-methoxy benzaldehyde on 6-OHDA induced neurotoxicity in Caenorhabditis elegans

In this study, we investigated the possible neuroprotective efficacy of Decalepis hamiltonii tuber extract against 6-Hydroxy dopamine (6-OHDA) induced neurotoxicity and associated effects in Caenorhabditis elegans. The major component of flavour rich extract from D. hamiltonii is 2-hydroxy-4-methoxy benzaldehyde (2H4MB) which is an isomer of vanillin. We have conducted preliminary experiments with different types of extracts and subsequently DHFE (D. hamiltonii Fresh Tuber Extract) and DHPF (D. hamiltonii purified 2H4MB fraction) were used for further studies. Here we attempted to enumerate the neuroprotective efficacy of the above compounds in worms by evaluating behavioural and mitochondrial function, dopamine content and selective degeneration of dopaminergic neurons in BZ555 strains in comparison with control and 6-OHDA treated organisms. The relative expression levels of selected antioxidant genes involved in defence mechanism like SOD-3, GST-2 and GST-4 were evaluated along with those of CAT-2 and DOP-2 at mRNA level. We observed that both DHPF and DHFE exhibited significant levels of neuroprotective property against 6-OHDA induced neurotoxicity, which was evident in mitochondrial/dopaminergic function and antioxidant defence mechanism.

Antiaflatoxigenic and Antimicrobial Activities of Schiff Bases of 2-Hydroxy-4-methoxybenzaldehyde, Cinnamaldehyde, and Similar Aldehydes

2-Hydroxy-4-methoxybenzaldehyde (HMBA) is a nontoxic phenolic flavor from dietary source Decalipus hamiltonii and Hemidesmus indicus. HMBA is an excellent antimicrobial agent with additional antiaflatoxigenic potency. On the other hand, cinnamaldehyde from cinnamon is a widely employed flavor with significant antiaflatoxigenic activity. We have attempted the enhancement of antiaflatoxigenic and antimicrobial properties of HMBA, cinnamaldehyde, and similar molecules via Schiff base formation accomplished from condensation reaction with amino sugar (d-glucamine). HMBA derived Schiff bases exhibited commendable antiaflatoxigenic activity at the concentration 0.1 mg/mL resulting in 9.6 ± 1.9% growth of Aspergillus flavus and subsequent 91.4 ± 3.9% reduction of aflatoxin B₁ with respect to control.

Physiologically induced changes in bound phenolics and antioxidants, DNA/cytoprotective potentials in pectic poly/oligosaccharides of tomato (Solanum lycopersicum)

BACKGROUND

Antioxidant, cyto/DNA protective potentials are known to offer significant protection against free radical induced injury to cells or tissues and cellular damages that are envisaged in various diseases including chronic diseases like cancer, diabetes, etc, while galectin-3 inhibitory potentials are known to block or delay the process of metastasis in cancer. Antioxidant, cyto/DNA protection and galectin-3 inhibitory potentials were examined in pectic polysaccharides (PPs) and pectic oligosaccharides (POs) from four types of two varieties of tomatoes such as Sour (Mallika local variety) raw (SrRT-SrRTPP, SrRTPO), Sour ripe (SrRIT-SrRITPP, SrRITPO), Sweet (Rashmi local variety) raw (SwRT-SwRTPP, SwRTPO) and Sweet ripe (SwRIT-SwRITPP and SwRITPO).

RESULTS

Results indicate that unripe PPs and POs show approximately four- to five-fold better galectin-3 inhibitory property than ripe ones. An approximately nine- to 10-fold increase in galectin-3 inhibitory activity in sour variety was observed. The IC₅₀ as determined by free radical scavenging (FRS), red blood cell (RBC) and DNA protection assays revealed reduction in FRS and RBC protective potencies in pectic oligosaccharides (POs) than pectic polysaccharides (PPs), supporting the fact that phenolics contribute towards these activities. Loss of activity could be attributed to the hydrolysis of certain phenolics during the ripening process as well as during conversion of PPs to POs.

CONCLUSION

This study, for the first time, showed changes in bioactivity profiling in unripened and ripened conditions in tomato. Precise alterations in biomolecular components, such as bound cinnamyl/ferulyl and vanillic acid derivatives, along with alterations in sugar composition that reflect changes in antioxidants, cyto/DNA protective and antimetastatic potentials, have been delineated. © 2016 Society of Chemical Industry.

Inhibitory potential of Buffalo (Bubalus bubalis) colostrum immunoglobulin G on Klebsiella pneumoniae

The unique components of colostrum like free oligosaccharides and glycoconjugates are known to offer resistance to enzymatic digestion in the gastrointestinal tract and have the ability to inhibit the localized adherence of enteropathogens to the digestive tract of the neonates. In this context, we have evaluated the in vitro effect of buffalo colostrum immunoglobulin G on human pathogen Klebsiella pneumoniae, a predominant multidrug resistant pathogen associated with nasocomial infections. The investigation revealed growth inhibitory potential of immunoglobulin G in a dose dependent manner supported by scanning electron microscopic studies. The N-glycan enriched fraction of immunoglobulin G after PNGase treatment was found more effective, comparable to ampicillin than native immunoglobulin G supporting the fact that colostrum derived oligosaccharides is crucial and act as ideal substrates for undesirable and pathogenic bacteria. The MALDI TOF/TOF analysis confirmed the glycostructures of abundant N-glycans of immunoglobulin G exerting antibacterial activity. The proteomic analysis revealed variations between control and treated cells and expression of chemotaxis-CheY protein (14kDa) was evidenced in response to immunoglobulin G treatment. Hence, it would be interesting to investigate the mode of inhibition of multidrug-resistant K. pneumoniae by buffalo colostrum immunoglobulin G with the identification of a newly expressed signalling protein.

Natural products and food components with anti-Helicobacter pylori activities

The bacterial pathogen Helicobacter pylori (H. pylori) colonizes in over half of the world’s population. H. pylori that establishes life-long infection in the stomach is definitely associated with gastro-duodenal diseases and a wide variety of non-gastrointestinal tract conditions such as immune thrombocytopenia. Triple therapy which consists of a proton pump inhibitor and combinations of two antibiotics (amoxicillin, clarithromycin or amoxicillin, metronidazol) is commonly used for H. pylori eradication. Recently, the occurrence of drug-resistant H. pylori and the adverse effect of antibiotics have severely weakened eradication therapy. Generally antibiotics induce the disturbance of human gastrointestinal microflora. Furthermore, there are inappropriate cases of triple therapy such as allergy to antibiotics, severe complications (liver and/or kidney dysfunction), the aged and people who reject the triple therapy. These prompt us to seek alterative agents instead of antibiotics and to develop more effective and safe therapy with these agents. The combination of these agents actually may result in lower a dose of antibiotics. There are many reports world-wide that non-antibiotic substances from natural products potentially have an anti-H. pylori agent. We briefly review the constituents derived from nature that fight against H. pylori in the literature with our studies.

Using antimicrobial adjuvant therapy in cancer treatment: a review

Recent clinical and pre-clinical data demonstrate that adjuvant antimicrobial therapy is beneficial in cancer treatment. There could be several reasons for this effect, which include treating cancer associated bacteria and viruses, prophylaxis of post-chemotherapy infections due to immunosuppression, and antiproliferative effect of certain antimicrobials. Targeting cancer associated viruses and bacteria with antimicrobial agents is currently used for gastric, cervical, hematopoietic, liver and brain cancer. However this treatment is effective only in combination with conventional therapies. Antimicrobials can also have a direct antiproliferative and cytotoxic effect, and can cause apoptosis. Moreover, some antimicrobials are known to be helpful in overcoming side effects of drugs commonly used in cancer treatment. Chemotherapy related bacteremia and neutropenia can be overcome by the appropriately timed use of antimicrobials. This review summarizes the data on the effects of antivirals and antibiotics on cancer treatment and describes their mechanisms.