Multifunctional MoS2 nanosheets with Au NPs grown in situ for synergistic chemo-photothermal therapy

The treatment of cancer has always been a worldwide problem. The combination of chemotherapy and other therapies would be a promising therapy strategy. Photothermal therapy (PTT) does not cause serious side effects and has dual control of time and space, which was considered to be a good method for combination with chemotherapy. Here, we modified multifunctional nanosheets based on in-situ gold nanoparticles (Au NPs) grown molybdenum disulfide (MoS₂) to combine their excellent photothermal conversion and drug loading capabilities. More importantly, the target peptide cRGD modified nanosheets have good selectivity to tumor cells rich in integrin receptors, and drug loading and drug release tests showed that it could carry enough chemotherapeutic drugs and had excellent photo controlled release performance. In vitro cell experiments showed that the drug-loaded multifunctional nanosheets had good anti-tumor effect under 808 nm laser irradiation. Therefore, the multifunctional nanosheets designed in this paper have great potential in the study of targeted drug release and chemo-photothermal therapy combined therapy, and are of great significance for in vivo and clinical research.

Chemotherapy for metastatic colon cancer: No effect on survival when the dose is reduced due to side effects

BACKGROUND

5-Fluorouracil (5FU), Folinic acid (FA), and Oxaliplatin (FOLFOX) or 5FU, FA, and Irinotecan (FOLFIRI) are standard regimens for palliative chemotherapy of metastatic colon cancer. Since data showing the influence of dose reduction in palliative treatment are rare, the objective of this single center, retrospective study was to further characterize the influence of dose reduction on efficacy of these therapeutic regimens.

METHODS

One hundred nine patients, diagnosed with stage IV colon cancer between 2004 and 2012 and receiving palliative first-line chemotherapy with either FOLFOX or FOLFIRI regimens in our outpatient clinic were analyzed for treatment efficacy. Patients who received dose reductions due to side effects usually received doses of 80% or lower of per protocol dose. Survival data were obtained from the Regensburg Tumor Registry. Survival analysis was performed using Kaplan-Meier statistical analysis and multivariable analysis.

RESULTS

A dose reduction due to side effects was necessary in 46 (42%) patients. Dose reduction was independent of age. Major reasons for dose reduction were neutropenia (30%) followed by polyneuropathy (16%) and diarrhea (14%). Dosage was more often reduced in patients receiving FOLFOX based therapy. Comparison of patients with dose reduction versus patients with full dosage showed no significant difference on overall survival (p = 0.430). Subgroup analysis revealed dose reduction in patients with N2 stage disease was associated with improved survival. Patients who underwent dose reduction received more cycles of chemotherapy (13.7 vs. 10.8 cycles) and cumulative dosage was similar in both groups.

CONCLUSION

Contrary to our expectations, the need to reduce chemotherapy dosage due to side effects does not indicate a worse prognosis in our retrospective analysis. We believe this can in part be explained by better adaption to interindividual pharmacokinetics and longer time of treatment.