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Expression of altered glycans such as TF, Tn, and sTn antigens has been observed in a number of carcinomas which are targeted in cancer therapy. Sclerotium rolfsii lectin (SRL) is known to recognize TF and its substituted forms. Clinical potential of SRL has been demonstrated by studying its interaction with different types of cancer cells. Here we report, in vitro studies of SRL on breast cancer MDA‐MB‐468 cells and in vivo studies with MCF‐7 xenografts. In vitro growth inhibitory studies of SRL on metastatic triple negative breast cancer MDA‐MB‐468 cells were performed by MTT assay, flow cytometry, adhesion, and CAM assay. In vivo efficacy studies of SRL were performed using NOD SCID mice bearing MCF‐7 xenografts. SRL has strong binding to MDA‐MB‐468 cells with MFI of 85.5 and has growth inhibitory effect with IC50 of 32 μg/ml at 48 hr. SRL has antiangiogenesis effect and also anti adhesive effect with fibronectin and collagen at 20 μg/ml by 36% and 42%, respectively. In vivo efficacy studies of SRL on NOD SCID mice bearing MCF‐7 xenogratfs revealed 61.77% and 75.71% tumor regressing effect, respectively, at 20 and 30 mg/kg body weight without any toxicity. All these results substantiate clinical potential of SRL on breast cancer. [ABSTRACT FROM AUTHOR]

The complex allotetraploid nature of the cotton genome makes genetic, genomic and functional analyses extremely challenging. Until now, several methods have been published for the purpose, but none is found to be universally applicable. To overcome these difficulties, we have designed protocol for the isolation of high quality and quantity genomic DNA from young as well as older leaves, which is suitable for molecular biology applications. We modified and optimized the CTAB method for plant genomic DNA extraction in large quantity and described protocol takes less than 80 min and does not require RNase treatment and purification step. The DNA yield ranged between 700-800 μg per gram of leaf tissue. Quantification of isolated DNA from spectral (A260/A280) measurements as well as agarose gel electrophoresis showed negligible polysaccharide and protein contamination. Thus the extracted DNA was very much suitable for southern hybridization and PCR based applications. [ABSTRACT FROM AUTHOR]

SRL is a cell wall associated developmental-stage specific lectin secreted by Sclerotium rolfsii, a soil-born pathogenic fungus. SRL displays specificity for TF antigen (Galβ1→3GalNAc-α-Ser//Thr) expressed in all cancer types and has tumour suppressing effects in vivo. Considering the immense potential of SRL in cancer research, we have generated two variant gene constructs of SRL and expressed in E. coli to refine the sugar specificity and solubility by altering the surface charge. SSR1 and SSR2 are two different recombinant variants of SRL, both of which recognize TF antigen but only SSR1 binds to Tn antigen (GalNAcα-Ser/Thr). The glycan array analysis of the variants demonstrated that SSR1 recognizes TF antigen and their derivative with high affinity similar to SRL but showed highest affinity towards the sialylated Tn antigen, unlike SRL. The carbohydrate binding property of SSR2 remains unaltered compared to SRL. The crystal structures of the two variants were determined in free form and in complex with N-acetylglucosamine at 1.7 Å and 1.6 Å resolution, respectively. Structural analysis highlighted the structural basis of the fine carbohydrate specificity of the two SRL variants and results are in agreement with glycan array analysis. [ABSTRACT FROM AUTHOR]

Amphotericin and curcumin are known to form complexes with albumins individually. In-silico analysis shows that amphotericin B and curcumin have separate binding regions on human serum albumin and bovine serum albumin. The complex formed with albumin in the presence of both amphotericin and curcumin is water soluble, and it retains antifungal activity. Interestingly, it was found that the presence of curcumin in the complex significantly delayed the red cell lysis by amphotericin B, indicating the possibility of moderating the toxic side effects of the drug using curcumin. Furthermore, since the presumed ternary complex is stable and water soluble, its potential use in the treatment of visceral leishmaniasis (kala azar) and systemic fungal infections needs to be evaluated. [ABSTRACT FROM AUTHOR]

Ophthalmic mycoses caused by infectious fungi are being recognized as a serious concern since they lead to total blindness. Cephalosporium is one amongst several opportunistic fungal species implicated in ophthalmic infections leading to mycotic keratitis. A mitogenic lectin has been purified from the mycelia of fungus Cephalosporium, isolated from the corneal smears of a keratitis patient. Cephalosporium lectin (CSL) is a tetramer with subunit mass of 14 kDa, agglutinates human A, B, and O erythrocytes, and exhibits high affinity formucin compared to fetuin and asialofetuin but does not bind to simple sugars indicating its complex sugar specificity. CSL showed strong binding to normal human peripheral blood mononuclear cells (PBMCs) to elicit mitogenic activity. The sugar specificity of the lectin and its interaction with PBMCs to exhibit mitogenic effect indicate its possible role in adhesion and infection process of Cephalosporium. [ABSTRACT FROM AUTHOR]

Sclerotium rolfsii lectin (SRL), from the soil-borne phytopathogenic fungus S. rolfsii, has been crystallized. SRL crystals were grown by the hanging-drop vapour-diffusion method using an MPD-ammonium acetate mixture in Tris-HC1 buffer pH 8.5. A complete data set from a single crystal at 100 K was collected to 1.1. A resolution using synchrotron radiation. Preliminary crystallographic analysis showed that the crystals belong to the tetragonal spoace group P4[sub 2]2[sub 1]2, with unit-cell parameters a = b = 99.81, c = 63.99 A and two molecules per asymmetric unit. [ABSTRACT FROM AUTHOR]

Sclerotium rolfsii lectin (SRL) is a lectin isolated from the fungus Sclerotium rolfsii and has exquisite binding specificity towards the oncofetal Thomsen-Friedenreich antigen (TF-Ag; Galβ1-3GalNAcα-O-Ser/Thr) and its derivatives. Previous studies have shown that SRL inhibits the proliferation of human colon, breast and ovarian cancer cells in vitro and suppresses tumour growth in mice when introduced intratumourally. The present study assessed the effect of SRL on tumour growth when introduced intraperitoneally in BALB/c nude mice and investigated the pharmacokinetics and biodistribution of SRL in Swiss albino mice. When 9 doses of SRL (30 mg/kg body weight/mice) was administered to BALB/c nude mice bearing human colon cancer HT-29 xenografts, a substantial reduction in tumour size was observed. A 35.8% reduction in tumour size was noted in the treated animals after 17 days. SRL treatment also inhibited angiogenesis, and the tumours from the treated animals were observed to carry fewer blood vessels and express less angiogenesis marker protein CD31, than that from the control animals. Pharmacokinetics and biodistribution analysis revealed that SRL was detected in the serum after 1 h and its level peaked after 24 h. SRL was not detected in any of the organs apart from the kidney where a trace amount was detected after 24 h of SRL injection. No significant changes were observed in any of the biochemical parameters tested including SGOT, SGPT, LDH, CREAT and BUN in the SRL-treated mice compared to these levels in the controls. This suggests that SRL has good potential to be developed as a therapeutic agent for cancer treatment and warrant further investigations in vivo and subsequent clinical trials.

Amphotericin and curcumin are known to form complexes with albumins individually. In-silico analysis shows that amphotericin B and curcumin have separate binding regions on human serum albumin and bovine serum albumin. The complex formed with albumin in the presence of both amphotericin and curcumin is water soluble, and it retains antifungal activity. Interestingly, it was found that the presence of curcumin in the complex significantly delayed the red cell lysis by amphotericin B, indicating the possibility of moderating the toxic side effects of the drug using curcumin. Furthermore, since the presumed ternary complex is stable and water soluble, its potential use in the treatment of visceral leishmaniasis (kala azar) and systemic fungal infections needs to be evaluated.