An evaluation in vitro of the efficacy of nutlin-3 and topotecan in combination with 177Lu-DOTATATE for the treatment of neuroblastoma

Abstract

Targeted radiotherapy of metastatic neuroblastoma using the somatostatin receptor (SSTR)-targeted octreotide analogue DOTATATE radiolabelled with lutetium-177 (177Lu-DOTATATE) is a promising strategy.

This study evaluates whether its effectiveness may be enhanced by combination with radiosensitising drugs.

The growth rate of multicellular tumour spheroids, derived from the neuroblastoma cell lines SK-N-BE(2c), CHLA-15 and CHLA-20, was evaluated following treatment with 177Lu-DOTATATE, nutlin-3 and topotecan alone or in combination.

Immunoblotting, immunostaining and flow cytometric analyses were used to determine activation of p53 signalling and cell death.

Exposure to 177Lu-DOTATATE resulted in a significant growth delay in CHLA-15 and CHLA-20 spheroids, but not in SK-N-BE(2c) spheroids. Nutlin-3 enhanced the spheroid growth delay induced by topotecan in CHLA-15 and CHLA-20 spheroids, but not in SK-N-BE(2c) spheroids. Importantly, the combination of nutlin-3 with topotecan enhanced the spheroid growth delay induced by X-irradiation or by exposure to 177Lu-DOTATATE.

The efficacy of the combination treatments was p53-dependent.

These results indicate that targeted radiotherapy of high risk neuroblastoma with 177Lu-DOTATATE may be improved by combination with the radiosensitising drugs nutlin-3 and topotecan.

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See also:

- Somatostatin in oncology, the overlooked evidences;

- The Di Bella Method (A Fixed Part - Somatostatin, Octreotide, LAR analogues and/or derivatives);

- The Di Bella Method (A Fixed Part - Cyclophosphamide and/or Hydroxyurea tablets, one or two per day);

- Neuroblastoma: Complete objective response to biological treatment;

- The Di Bella Method DBM improved survival objective response and performance status in a retrospective observational clinical study on 23 tumours of the head and neck;

- The Di Bella Method (DBM) in the treatment of prostate cancer: a preliminary retrospective study of 16 patients and a review of the literature;

- Oesophageal squamocellular carcinoma: a complete and objective response;

- Pleural Mesothelioma: clinical records on 11 patients treated with Di Bella's Method;

- Malignant pleural mesothelioma, stage T3-T4. Consideration of a case study;

- Excellent result in a Mesothelioma case treated exclusively with Di Bella Method for over 4 years and still treatment with positive results;

- Somatostatin, retinoids, melatonin, vitamin D, bromocriptine, and cyclophosphamide in advanced non-small-cell lung cancer patients with low performance status;

- Somatostatin, retinoids, melatonin, vitamin D, bromocriptine, and cyclophosphamide in chemotherapy-pretreated patients with advanced lung adenocarcinoma and low performance status;

- Observations on the Report of a case of pulmonary adenocarcinoma with lymph node, hepatic and osseus metastasis;

- Recurrent Glioblastoma Multiforme (grade IV – WHO 2007): a case of complete objective response achieved by means of the concomitant administration of Somatostatin and Octreotide – Retinoids – Vitamin E – Vitamin D3 – Vitamin C – Melatonin – D2 R agonists (Di Bella Method – DBM) associated with Temozolomide.

An evaluation in vitro of the efficacy of nutlin-3 and topotecan in combination with 177Lu-DOTATATE for the treatment of neuroblastoma - Supplementary Materials