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Immunotherapy of HPV-associated cancer: DNA/plant-derived vaccines and new orthotopic mouse models.

Venuti A, Curzio G, Mariani L, Paolini F - Cancer Immunol. Immunother. (2015)

Bottom Line: Under the optimistic assumption of high-prophylactic HPV vaccine coverage, a significant reduction of cancer incidence can only be expected after decades.Thus, immune therapeutic strategies are needed for persistently infected individuals who do not benefit from the prophylactic vaccines.In particular, the head/neck orthotopic model appears to be very promising for studies combining chemo-radio-immune therapy that seems to be very effective in patients.

View Article: PubMed Central - PubMed

Affiliation: HPV-UNIT, Laboratory of Virology, Regina Elena National Cancer Institute, Via E. Chianesi 53, 00144, Rome, Italy, venuti@ifo.it.

ABSTRACT
Under the optimistic assumption of high-prophylactic HPV vaccine coverage, a significant reduction of cancer incidence can only be expected after decades. Thus, immune therapeutic strategies are needed for persistently infected individuals who do not benefit from the prophylactic vaccines. However, the therapeutic strategies inducing immunity to the E6 and/or E7 oncoprotein of HPV16 are more effective for curing HPV-expressing tumours in animal models than for treating human cancers. New strategies/technologies have been developed to improve these therapeutic vaccines. Our studies focussed on preparing therapeutic vaccines with low-cost technologies by DNA preparation fused to either plant-virus or plant-toxin genes, such as saporin, and by plant-produced antigens. In particular, plant-derived antigens possess an intrinsic adjuvant activity that makes these preparations especially attractive for future development. Additionally, discrepancy in vaccine effectiveness between animals and humans may be due to non-orthotopic localization of animal models. Orthotopic transplantation leads to tumours giving a more accurate representation of the parent tumour. Since HPV can cause cancer in two main localizations, anogenital and oropharynx area, we developed two orthotopic tumour mouse models in these two sites. Both models are bioluminescent in order to follow up the tumour growth by imaging and are induced by cell injection without the need to intervene surgically. These models were utilized for immunotherapies with genetic or plant-derived therapeutic vaccines. In particular, the head/neck orthotopic model appears to be very promising for studies combining chemo-radio-immune therapy that seems to be very effective in patients.

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Related in: MedlinePlus

Genital mouse model of HPV-associated cancer. TC-1* cells were infected with Lenti-Luc vector to generate TC-1*-Luc cells. a Different concentrations of TC-1*-Luc cells (triplicates) were plated in 96-well plates, and D-luciferin (final concentration of 0.15 mg/ml) was added 15 min before monitoring. Bioluminescence was measured by imaging system and calculated as photons/s/cm2/sr. Each point is mean ± SD. b Diestrum synchronized eight-week-old female C57BL/6 mice were pre-treated with a spermicidal/detergent N9 (4 %), and after 6 h washed with phosphate-buffered saline before challenging with 5 × 104 TC-1*-Luc cells. Genital tumour growth was monitored at the indicated time interval post-challenge. Bioluminescence was measured 15 min after intraperitoneal injection of D-luciferin by imaging system and quantified as photons/s/cm2/sr in a colour scale
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Fig1: Genital mouse model of HPV-associated cancer. TC-1* cells were infected with Lenti-Luc vector to generate TC-1*-Luc cells. a Different concentrations of TC-1*-Luc cells (triplicates) were plated in 96-well plates, and D-luciferin (final concentration of 0.15 mg/ml) was added 15 min before monitoring. Bioluminescence was measured by imaging system and calculated as photons/s/cm2/sr. Each point is mean ± SD. b Diestrum synchronized eight-week-old female C57BL/6 mice were pre-treated with a spermicidal/detergent N9 (4 %), and after 6 h washed with phosphate-buffered saline before challenging with 5 × 104 TC-1*-Luc cells. Genital tumour growth was monitored at the indicated time interval post-challenge. Bioluminescence was measured 15 min after intraperitoneal injection of D-luciferin by imaging system and quantified as photons/s/cm2/sr in a colour scale

Mentions: The genital orthotopic model was originally developed by Decrausaz et al. [53], and we have reproduced the same model with our TC-1* star cells that are more aggressive than the parental TC-1 cells, giving 100 % of tumour upon inoculation in the flank of mice [48]. Briefly, TC-1* cells were infected by luciferase-encoding lentiviral vector producing bioluminescent cells for in vivo imaging of tumour growth (Fig. 1a). After in vitro passages, TC-1*-Luc cells were transplanted into the mouse vagina pre-treated with nonoxynol-9 (N9) in order to disrupt transiently the vaginal epithelium favouring the trapping of injected cells and the development of luminescent vaginal tumours. An example of this orthotopic HPV-associated mouse genital tumour is presented in Fig. 1b. This model was not further developed due to the arduous task of dealing with the experimental procedures, and in our hands, sometimes the tumour expands into the peritoneal area broadening the gap between the model and the human pathology. Moreover, TC-1 cells did not derive from the same anatomical area, and they did not represent a proper orthotopic transplantation. However, this model retains the immunological features of naturally occurring HPV tumours [53].Fig. 1


Immunotherapy of HPV-associated cancer: DNA/plant-derived vaccines and new orthotopic mouse models.

Venuti A, Curzio G, Mariani L, Paolini F - Cancer Immunol. Immunother. (2015)

Genital mouse model of HPV-associated cancer. TC-1* cells were infected with Lenti-Luc vector to generate TC-1*-Luc cells. a Different concentrations of TC-1*-Luc cells (triplicates) were plated in 96-well plates, and D-luciferin (final concentration of 0.15 mg/ml) was added 15 min before monitoring. Bioluminescence was measured by imaging system and calculated as photons/s/cm2/sr. Each point is mean ± SD. b Diestrum synchronized eight-week-old female C57BL/6 mice were pre-treated with a spermicidal/detergent N9 (4 %), and after 6 h washed with phosphate-buffered saline before challenging with 5 × 104 TC-1*-Luc cells. Genital tumour growth was monitored at the indicated time interval post-challenge. Bioluminescence was measured 15 min after intraperitoneal injection of D-luciferin by imaging system and quantified as photons/s/cm2/sr in a colour scale
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4554738&req=5

Fig1: Genital mouse model of HPV-associated cancer. TC-1* cells were infected with Lenti-Luc vector to generate TC-1*-Luc cells. a Different concentrations of TC-1*-Luc cells (triplicates) were plated in 96-well plates, and D-luciferin (final concentration of 0.15 mg/ml) was added 15 min before monitoring. Bioluminescence was measured by imaging system and calculated as photons/s/cm2/sr. Each point is mean ± SD. b Diestrum synchronized eight-week-old female C57BL/6 mice were pre-treated with a spermicidal/detergent N9 (4 %), and after 6 h washed with phosphate-buffered saline before challenging with 5 × 104 TC-1*-Luc cells. Genital tumour growth was monitored at the indicated time interval post-challenge. Bioluminescence was measured 15 min after intraperitoneal injection of D-luciferin by imaging system and quantified as photons/s/cm2/sr in a colour scale
Mentions: The genital orthotopic model was originally developed by Decrausaz et al. [53], and we have reproduced the same model with our TC-1* star cells that are more aggressive than the parental TC-1 cells, giving 100 % of tumour upon inoculation in the flank of mice [48]. Briefly, TC-1* cells were infected by luciferase-encoding lentiviral vector producing bioluminescent cells for in vivo imaging of tumour growth (Fig. 1a). After in vitro passages, TC-1*-Luc cells were transplanted into the mouse vagina pre-treated with nonoxynol-9 (N9) in order to disrupt transiently the vaginal epithelium favouring the trapping of injected cells and the development of luminescent vaginal tumours. An example of this orthotopic HPV-associated mouse genital tumour is presented in Fig. 1b. This model was not further developed due to the arduous task of dealing with the experimental procedures, and in our hands, sometimes the tumour expands into the peritoneal area broadening the gap between the model and the human pathology. Moreover, TC-1 cells did not derive from the same anatomical area, and they did not represent a proper orthotopic transplantation. However, this model retains the immunological features of naturally occurring HPV tumours [53].Fig. 1

Bottom Line: Under the optimistic assumption of high-prophylactic HPV vaccine coverage, a significant reduction of cancer incidence can only be expected after decades.Thus, immune therapeutic strategies are needed for persistently infected individuals who do not benefit from the prophylactic vaccines.In particular, the head/neck orthotopic model appears to be very promising for studies combining chemo-radio-immune therapy that seems to be very effective in patients.

View Article: PubMed Central - PubMed

Affiliation: HPV-UNIT, Laboratory of Virology, Regina Elena National Cancer Institute, Via E. Chianesi 53, 00144, Rome, Italy, venuti@ifo.it.

ABSTRACT
Under the optimistic assumption of high-prophylactic HPV vaccine coverage, a significant reduction of cancer incidence can only be expected after decades. Thus, immune therapeutic strategies are needed for persistently infected individuals who do not benefit from the prophylactic vaccines. However, the therapeutic strategies inducing immunity to the E6 and/or E7 oncoprotein of HPV16 are more effective for curing HPV-expressing tumours in animal models than for treating human cancers. New strategies/technologies have been developed to improve these therapeutic vaccines. Our studies focussed on preparing therapeutic vaccines with low-cost technologies by DNA preparation fused to either plant-virus or plant-toxin genes, such as saporin, and by plant-produced antigens. In particular, plant-derived antigens possess an intrinsic adjuvant activity that makes these preparations especially attractive for future development. Additionally, discrepancy in vaccine effectiveness between animals and humans may be due to non-orthotopic localization of animal models. Orthotopic transplantation leads to tumours giving a more accurate representation of the parent tumour. Since HPV can cause cancer in two main localizations, anogenital and oropharynx area, we developed two orthotopic tumour mouse models in these two sites. Both models are bioluminescent in order to follow up the tumour growth by imaging and are induced by cell injection without the need to intervene surgically. These models were utilized for immunotherapies with genetic or plant-derived therapeutic vaccines. In particular, the head/neck orthotopic model appears to be very promising for studies combining chemo-radio-immune therapy that seems to be very effective in patients.

Show MeSH
Related in: MedlinePlus