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- Hofving, Tobias, 1989, et al.
(författare)
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177 Lu-octreotate therapy for neuroendocrine tumours is enhanced by Hsp90 inhibition
- 2019
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Ingår i: Endocrine-Related Cancer. - 1479-6821 .- 1351-0088. ; 26:4, s. 437-449
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Tidskriftsartikel (refereegranskat)abstract
- Lu-177-octreotate is an FDA-approved radionuclide therapy for patients with gastroenteropancreatic neuroendocrine tumours (NETs) expressing somatostatin receptors. The Lu-177-octreotate therapy has shown promising results in clinical trials by prolonging progression-free survival, but complete responses are still uncommon. The aim of this study was to improve the Lu-177-octreotate therapy by means of combination therapy. To identify radiosensitising inhibitors, two cell lines, GOT1 and P-STS, derived from small intestinal neuroendocrine tumours (SINETs), were screened with 1224 inhibitors alone or in combination with external radiation. The screening revealed that inhibitors of Hsp90 can potentiate the tumour cell-killing effect of radiation in a synergistic fashion (GOT1; false discovery rate < 3.2 x 10(-11)). The potential for Hsp90 inhibitor ganetespib to enhance the anti-tumour effect of Lu-177-octreotate in an in vivo setting was studied in the somatostatin receptor-expressing GOT1 xenograft model. The combination led to a larger decrease in tumour volume relative to monotherapies and the tumour-reducing effect was shown to be synergistic. Using patient-derived tumour cells from eight metastatic SINETs, we could show that ganetespib enhanced the effect of Lu-177-octreotate therapy for all investigated patient tumours. Levels of Hsp90 protein expression were evaluated in 767 SINETs from 379 patients. We found that Hsp90 expression was upregulated in tumour cells relative to tumour stroma in the vast majority of SINETs. We conclude that Hsp90 inhibitors enhance the tumour-killing effect of Lu-177-octreotate therapy synergistically in SINET tumour models and suggest that this potentially promising combination should be further evaluated.
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| 2. |
- Sandblom, Viktor, 1987, et al.
(författare)
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Gemcitabine potentiates the anti-tumour effect of radiation on medullary thyroid cancer.
- 2019
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Ingår i: PloS One. - : Public Library of Science (PLoS). - 1932-6203. ; 14:11
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Tidskriftsartikel (refereegranskat)abstract
- Patients with medullary thyroid cancer (MTC) are often diagnosed with spread tumour disease and the development of better systemic treatment options for these patients is important. Treatment with the radiolabelled somatostatin analogue 177Lu-octreotate is already a promising option but can be optimised. For example, combination treatment with another substance could increase the effect on tumour tissue. Gemcitabine is a nucleoside analogue that has been shown to sensitise tumour cells to radiation. The aim of this study was to investigate potentially additive or synergistic effects of combining radiation with gemcitabine for treatment of MTC. Nude mice transplanted with patient-derived MTC tumours (GOT2) were divided into groups and treated with radiation and/or gemcitabine. Radiation treatment was given as 177Lu-octreotate or external beam radiotherapy (EBRT). The volume of treated and untreated tumours was followed. The absorbed dose and amount of gemcitabine were chosen to give moderate tumour volume reduction when given as monotherapy to enable detection of increased effects from combination treatment. After follow-up, the mice were killed and tumours were immunohistochemically (IHC) analysed. Overall, the animals that received a combination of EBRT and gemcitabine showed the largest reduction in tumour volume. Monotherapy with EBRT or gemcitabine also resulted in a clear detrimental effect on tumour volume, while the animals that received 177Lu-octreotate monotherapy showed similar response as the untreated animals. The GOT2 tumour was confirmed in the IHC analyses by markers for MTC. The IHC analyses also revealed that the proliferative activity of tumour cells was similar in all tumours, but indicated that fibrotic tissue was more common after EBRT and/or gemcitabine treatment. The results indicate that an additive, or even synergistic, effect may be achieved by combining radiation with gemcitabine for treatment of MTC. Future studies should be performed to evaluate the full potential of combining 177Lu-octreotate with gemcitabine in patients.
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| 3. |
- Sandblom, Viktor, 1987, et al.
(författare)
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Increased therapeutic effect on medullary thyroid cancer using a combination of radiation and tyrosine kinase inhibitors : Increased effect on medullary thyroid cancer by combining radiation with tyrosine kinase inhibitors
- 2020
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Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 15:5
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Tidskriftsartikel (refereegranskat)abstract
- Since patients with medullary thyroid cancer (MTC) often have metastatic disease at the time of diagnosis, the development of efficient systemic treatment options for MTC is important. Vandetanib and cabozantinib are two tyrosine kinase inhibitors (TKIs) that were recently approved by FDA and EMA for systemic treatment of metastatic MTC. Additionally, since MTC is of a neuroendocrine tumour type, treatment with radiolabelled somatostatin analogues (e.g. 177Lu-octreotate) is a valid option for patients with MTC. The aim of this study was to investigate the potentially increased therapeutic effect of combining radiation therapy with these TKIs for treatment of MTC in a mouse model. Nude mice carrying patient-derived MTC tumours (GOT2) were treated with external beam radiotherapy (EBRT) and/or one of the two TKIs vandetanib or cabozantinib. The tumour volume was determined and compared with that of mock-treated controls. The treatment doses were chosen to give a moderate effect as monotherapy to be able to detect any increased therapeutic effect from the combination therapy. At the end of follow-up, tumours were processed for immunohistochemical (IHC) analyses. The animals in the combination therapy groups showed the largest reduction in tumour volume and the longest time to tumour progression. Two weeks after start of treatment, the tumour volume for these mice was reduced by about 70-75% compared with controls. Furthermore, also EBRT and TKI monotherapy resulted in a clear anti-tumour effect with a reduced tumour growth compared with controls. The results show that an increased therapeutic effect could be achieved when irradiation is combined with TKIs for treatment of MTC. Future studies should evaluate the potential of using 177Lu-octreotate therapy in combination with TKIs in patients.
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| 5. |
- Sandblom, Viktor, 1987, et al.
(författare)
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Tyrosinkinashämmare kan öka effekten från strålbehandling av medullär tyreoideacancer
- 2019
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Ingår i: Nationellt möte om sjukhusfysik.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- SYFTE Medullär tyreoideacancer (MTC) är en neuroendokrin cancertyp som har sitt ursprung i sköldkörtelns hormonproducerande C-celler. Många MTC överuttrycker receptorer för somatostatin vilket möjliggör radionuklidterapi med exempelvis 177Lu-oktreotat. Få patienter botas dock helt och optimering av behandlingen behövs. Ett sätt att optimera behandlingen är att kombinera 177Lu-oktreotat med ett annat läkemedel i syfte att öka effekten från strålningen. Nyligen godkändes två tyrosinkinashämmare (vandetanib och cabozantinib) för behandling av MTC. Syftet med denna studie var att undersöka ifall en ökad effekt kan fås då strålbehandling kombineras med tyrosinkinashämmare för behandling av MTC. METOD Nakna möss (BALB/c) transplanterades med humana MTC-celler (GOT2) och behandlades med extern strålbehandling och/eller tyrosinkinashämmare. Behandlings-effekten, som tumörvolym efter behandling, jämfördes med den hos obehandlade möss. För att möjliggöra detektion av en eventuellt ökad behandlingseffekt hos de möss som fick kombinationsbehandling (både strålbehandling och tyrosinkinas¬hämmare) valdes den absorberade dosen och mängden läkemedel så att en suboptimal effekt erhölls då respektive behandling gavs som singelbehandling. RESULTAT Kombinationsbehandling resulterade i störst minskning av tumörvolym och längst tid till progression. Exempelvis hade tumörvolymen hos de möss som fick kombinationsbehandling minskat med ca 70-75% efter två veckor jämfört med obehandlade möss. Även som singelbehandling resulterade båda behandlingar i en tydlig effekt på tumörvolymen, med en minskning på ca 50-65% efter två veckor. KONKLUSIONER Effekten från strålbehandling av möss med MTC-tumörer kan ökas genom kombinationsbehandling med tyrosinkinashämmare. Framtida studier bör utvärdera möjligheten att använda en kombination av 177Lu-oktreotat och tyrosinkinashämmare för behandling av patienter med MTC.
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