A Phase I Study of Irinotecan, Capecitabine (Xeloda), and Oxaliplatin in Patients With Advanced Colorectal Cancer

Rationally Designed Oral DOX Gels for Colon-Specific Administration

Colorectal cancer (CRC) is the third leading cause of death from cancer in both men and women. Traditional CRC dosage forms deliver the drug to both desired and unwanted sites of drug action, resulting in a number of negative side effects. Chemotherapeutic and chemopreventive agents are being targeted and delivered directly to the colon and rectum using targeted oral drug delivery systems. The main challenge in successfully targeting drugs to the colon via the oral route is avoiding drug absorption/degradation in the stomach and small intestine before the dosage form reaches the colon. In this study, we employed biocompatible chalk to adsorb DOX, then mixed pectin and cross-linked with calcium ions to form PC-DOX gels. The presence of cross-linked pectin and chalk can provide dual protection for the drug, significantly reducing drug leakage in gastric acid. In vitro release results showed that the designed PC-DOX could achieve 68% colon delivery efficiency. In the simulated colon environment, the released semi-degradable chalk did not affect the uptake of doxorubicin by colon cancer cells. Finally, in vivo simulation experiments in mice showed that rationally designed PC-DOX could achieve the highest colonic delivery efficiency. Our strategy has great potential for application in the treatment of colon cancer.

Microfluidized Dextran Microgels Loaded with Cisplatin/SPION Lipid Nanotherapeutics for Local Colon Cancer Treatment via Oral Administration

Multifunctional sequential targeted delivery system is developed as an efficient therapeutic strategy against malignant tumors with selective accumulation and minimal systemic drug absorption. The therapeutic system is comprised of microfluidized dextran microgels encapsulating cisplatin/superparamagnetic iron oxide nanoparticles (SPIONs)-loaded trilaurin-based lipid nanoparticles (LNPs). The microgel system is imparted hierarchically dual targeting via dextran and folic acid (FA) residues, leading to increases both in retention of the microgels in colon and in cellular uptake of the therapeutic LNPs by colon cancer cells while being used for oral therapeutic delivery. Encapsulation of the therapeutic LNPs into dextran microgels attained by microfluidized crosslinking reaction reduces gastrointestinal adhesion and prevents the FA-modified LNPs from cellular transport by proton-coupled FA transporters in small intestine during their oral delivery to colon. Upon enzymatic degradation of the dextran microgels by dextranase present exclusively in colon, LNPs thus released become more recognizable and readily internalized by FA receptor-overexpressing colon cancer cells. The combined chemo/magnetothermal therapeutic effect of dual targeted lipid nanoparticle-loaded microgels from entrapped lipidized cisplatin and alternating magnetic field-treated SPIONs significantly inhibits tumor growth and suppresses metastatic peritoneal carcinomatosis in orthotopic colon cancer-bearing mice.

Celastrol suppresses nitric oxide synthases and the angiogenesis pathway in colorectal cancer

The thunder god vine (Tripterygium wilfordii Hook. F) is traditionally used for inflammation-related diseases in traditional Chinese medicine. In recent years, celastrol (a natural compound from the root of the thunder god vine) has attracted great interest for its potential anticancer activities. The free radical nitric oxide (NO) is known to play a critical role in colorectal cancer growth by promoting tumour angiogenesis. However, how celastrol influences the NO pathway and its mechanism against colorectal cancer is largely unknown. In this study, we investigated the effects and mechanism of celastrol on nitric oxide synthase (NOS) and the angiogenesis pathway in colorectal cancer. Our data show that celastrol inhibited HT-29 and HCT116 cell proliferation, migration, and NOS activity in the cytoplasm. The antiproliferation activity of celastrol was associated with the inhibition of iNOS and eNOS in colorectal cancer cells. Treatment with celastrol inhibited colorectal cancer cell growth and migration, and was associated with suppression of the expression of key genes (TYMP, CDH5, THBS2, LEP, MMP9, and TNF) and proteins (IL-1b, MMP-9, PDGF, Serpin E1, and TIMP-4) involved in the angiogenesis pathway. In addition, combinational use of celastrol with 5-fluorouracil, salinomycin, 1400 W, and L-NIO showed enhanced inhibition of colorectal cancer cell proliferation and migration. In sum, our study suggests that celastrol could suppress colorectal cancer cell growth and migration, likely through suppressing NOS activity and inhibiting the angiogenesis pathway.

A multicentre, open-label phase II study of Irinotecan, capecitabine (Xeloda®), and Oxaliplatin (IXO) as first-line treatment in patients with metastatic gastric or gastroesophageal junction (GEJ) adenocarcinoma

Purpose Chemotherapy remains the primary treatment for metastatic gastric/GEJ cancer but optimal agents and schedule remain controversial. This study examined the safety and efficacy of first-line Irinotecan, capecitabine (Xeloda®), and Oxaliplatin (IXO). Patients and Methods Eligible patients with HER2-unamplified/unknown, metastatic gastric/GEJ adenocarcinoma were treated with 21-day cycle IXO at dose level 1 (DL1: Day 1 O-100 mg/m² & I-160 mg/m² IV, Day 2-15 X-1900 mg/m²/day PO divided doses) or modified IXO (mIXO): Day 1 O-85 mg/m² & I-120 mg/m² IV, Day 2-15 X-1425 mg/m²/day PO divided doses). This Bryant and Day two-stage designed study had dual primary endpoints of objective response rate (ORR) and toxicity. Secondary endpoints were overall survival (OS) and progression-free survival (PFS). Results Fifty patients were enrolled and received a median of 7 cycles. After accrual of 9 patients at DL1, evaluable RR was 88% however dose limiting toxicity (DLT) rate was 56% thus doses were adjusted to mIXO. Fifteen patients accrued at mIXO had a RR of 60% and DLT rate of 13% allowing continuation to stage 2. Overall, 48 and 49 patients were evaluable for efficacy and safety, respectively, with ORR of 54% and DLTs in 24% of patients (DL1 = 56%; mIXO = 18%). Disease control rate was 85%. The most frequent grade 3/4 adverse events were diarrhea, neutropenia, fatigue, hypokalemia, and nausea. Median PFS and OS were 7.5 and 13.0 months, respectively, with a median follow-up of 9.7 months. Conclusion mIXO demonstrates promising ORR, PFS, OS, and acceptable toxicity compared to standard triplet regimens. IXO should be evaluated in phase III trials.