Taxane analogues against breast cancer: a quantitative structure-activity relationship study

Synthesis and biological activity of C-7, C-9 and C-10 modified taxane analogues from 1-deoxybaccatin VI

A series of C-7, C-9 and C-10 modified taxane analogues were synthesized and their in vitro anticancer activities against three human cancer cell lines: A-549 (human lung cancer cell line), MDA-MB-231 (human breast cancer cell line), A-549/T (human lung cancer resistant cell line) were studied. The novel 1-deoxybaccatin VI derivatives modified with carbonate group at C-9 and C-10 positions enable the behavior of these compounds to be evidently distinct from other similar compounds. The strong cytotoxicity in the three cell lines, especially in drug-resistant cell line, showed by the newly synthesized taxane analogues indicated them as potential lead compounds for anticancer drug design.

Novel fluorinated docetaxel analog for anti-hepatoma: Molecular docking and biological evaluation

N-De-tert-butoxycarbonyl-N-[2-(1,1,1-trifluoro-2-methyl)propyloxycarbonyl]-2-debenzoyl-2-(m-fluorobenzoyl)-docetaxel (4FDT), a novel fluorinated docetaxel analog, was evaluated for its anti-hepatoma effect and possible druggability. In molecular docking studies, 4FDT coincided with paclitaxel in a part of the nucleus. In in vitro studies, 4FDT demonstrated higher anti-hepatoma activity approximately 1.5 times greater than that of docetaxel. More interestingly, 4FDT had been determined to have better anticancer effects, even 90 times greater in patient-derived xenografts (PDX) liver cancer cell lines than sorafenib. In the in vivo studies, 4FDT could effectively reduce the growth rate of liver cancer H22 and HepG2 cells. Furthermore, in a preliminary study on the ex vivo distribution of 4FDT, 4FDT-IR783 was primarily concentrated in the liver 1h after injection, and most of it was metabolized from the liver in 24h. Finally, the acute toxicity test revealed fewer side effects for 4FDT (approximately 16% than docetaxel). The water solubility, which was 11 times greater than that of docetaxel, confirmed the good druggability of 4FDT. All of these results demonstrated 4FDT's great potential to be a candidate drug for liver cancer treatment.

LZTS1 downregulation confers paclitaxel resistance and is associated with worse prognosis in breast cancer

The Leucine Zipper Tumor Suppressor 1 (LZTS1) is a tumor suppressor gene, located at chromosome 8p22, which is frequently altered in human cancer. In normal tissue, its ubiquitous expression regulates cell mitosis by the stabilization of microtubule networks. LZTS1-deficient mouse embryonic fibroblasts have been shown to have an accelerated mitotic progression, and a higher resistance to taxanes, microtubule-stabilizing drugs. We investigate the role of Lzts1 in paclitaxel-resistance in breast cancer cells. Downregulation of Lzts1 expression significantly decreases sensitivity to paclitaxel in vitro. We further analyzed Lzts1 expression by immunohistochemistry in 270 primary breast cancer samples and 16 normal breast specimens. Lzts1 was significantly downregulated in breast cancer samples and its deregulation was associated with a higher incidence of tumor recurrence, and to a worse overall survival. Moreover, Lzts1-negative tumors were associated with unfavorable outcome after taxanes-based therapy. Thus our data suggest that Lzts1 deregulation is involved in breast cancer and its immunohistochemical evaluation may serve as a prognostic factor for breast cancer therapy.

Dual Allosteric Effect in Glycine/NMDA Receptor Antagonism: A Comparative QSAR Approach

A comparative Hansch type QSAR study was conducted using multiple regression analysis on various sets of quinoxalines, quinoxalin-4-ones, quinazoline-2-carboxylates, 4-hydroxyquinolin-2(1H)-ones, 2-carboxytetrahydroquinolines, phenyl-hydroxy-quinolones, nitroquinolones and 4-substituted-3-phenylquinolin-2(1H)-ones as selective glycine/NMDA site antagonists. Ten statistically validated equations were developed, which indicated the importance of CMR, Verloop’s sterimol L1 and ClogP parameters in contributing towards biological activity. Interestingly, normal and inverse parabolic relationships were found with CMR in different series, indicating a dual allosteric binding mode in glycine/NMDA antagonism. Equations reveal an optimum CMR of 10 ± 10% is required for good potency of antagonists. Other equations indicate the presence of anionic functionality at 4-position of quinoline/quinolone ring system is not absolutely required for effective binding. The observations are laterally validated and in accordance with previous studies.

Overcoming tumor drug resistance with C2-modified 10-deacetyl-7-propionyl cephalomannines: a QSAR study

The microtubule-stabilizing taxanes such as paclitaxel and docetaxel are the two most important anticancer drugs currently used in clinics for the treatment of various types of cancers. However, the major common drawbacks of these two drugs are drug resistance, neurotoxicity, substrate for drug transporter P-gp, cross-resistance with other chemotherapeutic agents, low oral bioavailability, and no penetration in the blood-brain barrier (BBB). These limitations have led to the search for new taxane derivatives with improved biological activity. In the present paper, we discuss the quantitative structure-activity relationship (QSAR) studies on a series of C2-modified 10-deacetyl-7-propionyl cephalomannines (IV) with respect to their binding affinities toward beta-tubulin and cytotoxic activities against both drug-sensitive and drug-resistant tumor cells, in which resistance is mediated through either P-gp overexpression or beta-tubulin mutation mechanisms, by the formulation of five QSARs. Hydrophobicity and molar refractivity of the substituents (pi(X) and MR(X)) are found to be the most important determinants for the activity. Parabolic correlations in terms of MR(X) (eqs 2 and 4 ) are encouraging examples in which the optimum values of MR(X) are well-defined. We believe that these two QSAR models may prove to be adequate predictive models that can help to provide guidance in design and synthesis, and subsequently yield very specific cephalomannine derivatives (IV) that may have high biological activities. On the basis of these two QSAR models, 10 cephalomannine analogues (IV-21 to IV-30) are suggested as potential synthetic targets. Internal (cross-validation (q(2)), quality factor (Q), Fischer statistics (F), and Y-randomization) and external validation tests have validated all the QSAR models.

Taxane analogues against lung cancer: a quantitative structure-activity relationship study

Lung cancer is the second most common cancer in both men (after prostate cancer) and women (after breast cancer). The microtubule-stabilizing taxane such as docetaxel is the only agent currently approved for both first- and second-line treatment of advanced non-small cell lung cancer. Although docetaxel has made significant progress in the treatment of lung cancers either using alone or in combination with various novel targeted agents, its use often results in various undesired side-effects. These limitations have led to the search for new taxane derivatives with fewer side-effects, superior pharmacological properties, and improved anticancer activity to maximize the induced benefits for lung cancer patients. Herein, four series of taxane derivatives were used to correlate their inhibitory activities against lung cancer cells with hydrophobic and steric descriptors to gain a better understanding of their chemical-biological interactions. A parabolic correlation with MR(Y) is the most encouraging example, in which the optimum value of this parameter is well defined. On the basis of this quantitative structure-activity relationship model, six compounds (3-23 to 3-28) are suggested as potential synthetic targets. Internal (cross-validation (q(2)), quality factor (Q), Fischer statistics (F ) and Y-randomization) and external validation tests have validated all the quantitative structure-activity relationship models.