Biweekly combination of trastuzumab, docetaxel and gemcitabine for HER2-positive metastatic breast cancer: results of a Phase II GOIM study

Metronomic oral chemotherapy with cyclophosphamide plus capecitabine combined with trastuzumab (HEX) as first line therapy of HER-2 positive advanced breast cancer: A phase II trial of the Gruppo Oncologico Italia Meridionale (GOIM)

BACKGROUND

The combination of chemotherapy plus anti HER-2 agents is the mainstay of HER-2 positive advanced breast cancer (ABC) therapy. We conducted a phase II trial testing activity and safety of trastuzumab and metronomic capecitabine/cyclophosphamide (HEX) as first-line therapy in HER-2 positive ABC.
Methods. Patients at first relapse or with synchronous metastasis were treated with trastuzumab (4 mg/kg, biweekly) plus oral capecitabine (1500 mg/daily) and cyclophosphamide (50 mg/daily). Primary endpoint was objective response rate (ORR), secondary endpoints progression-free survival (PFS), clinical benefit rate (CBR; PR + CR + SD for ≥ 24 weeks) and tolerability. Optimal two-stage design was applied.

RESULTS

Sixty patients with measurable ABC, tumors scored as +3 for HER-2 or FISH +, untreated for advanced disease were enrolled. Median age was 62.5 years, visceral metastases were present in most patients (57.9%). Median number of cycles was 16 (range 1-98). ORR was 56.7% (95% CI, 44.1-68.4%), with 5 CR (8.3%) and 29 PR (48.3%). Fifteen patients had SD (25%). The CBR was 78.2%. Nine progressions were observed (15%). Median PFS was 11 months. One year PFS was 47.7%. Median OS was 45.9 months. Worst toxicities were grade 3 hand-foot syndrome in 2 pts (3.3%), grade 3 anaemia in 2 pts (3.3%), grade 2 nausea in 2 pts (3.3%) and grade 3-4 diarrhea in 2 pts (3.3%). Cardiac toxicity grade 1 was reported in 1 pt.

CONCLUSIONS

Combination of trastuzumab and metronomic oral chemotherapy has clinical activity. The tolerability was excellent and allowed the prolonged delivery of treatment.

Anti-Diarrheal Drug Repositioning in Tumour Cell Cytotoxicity

BACKGROUND

Drug repositioning is becoming an ideal strategy to select new anticancer drugs. In particular, drugs treating the side effects of chemotherapy are the best candidates.

OBJECTIVE

In this present work, we undertook the evaluation of anti-tumour activity of two anti-diarrheal drugs (nifuroxazide and rifaximin).

METHODS

Anti-proliferative effect against breast cancer cells (MDA-MB-231, MCF-7 and T47D) was assessed by MTT analysis, the Brdu incorporation, mitochondrial permeability and caspase-3 activity.

RESULTS

Both the drugs displayed cytotoxic effects on MCF-7, T47D and MDA-MB-231 cells. The lowest IC50 values were obtained on MCF-7 cells after 24, 48 and 72 hours of treatment while T47D and MDA-MB-231 were more resistant. The IC50 values on T47D and MDA-MB-231 cells became significantly low after 72 hours of treatment showing a late cytotoxicity effect especially of nifuroxazide but still less important than that of MCF-7 cells. According to the IC50 values, the non-tumour cell line HEK293 seems to be less sensitive to cytotoxicity especially against rifaximin. Both the drugs have shown an accumulation of rhodamine 123 as a function of the rise of their concentrations while the Brdu incorporation decreased. Despite the absence of a significant difference in the cell cycle between the treated and non-treated MCF-7 cells, the caspase-3 activity increased with the drug concentrations rise suggesting an apoptotic effect.

CONCLUSION

Nifuroxazide and rifaximin are used to overcome the diarrheal side effect of anticancer drugs. However, they have shown to be anti-tumour drugs which make them potential dual effective drugs against cancer and the side effects of chemotherapy.