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Lin, et al.
(nearly 20% more) at a Planic-GelMA ratio of 2:1, and based on the in vivo experiments, 89% of tumor cells
the hydrogel composite with this ratio provided a good in the MS-AKT group were necrotic, which was much
platform for cell attachment and proliferation. Non- higher than other controls. This bifunctional scaffold was
scaffold vascular-like structures are evolving as potential able to treat tumors and promote bone growth, providing
vascular alternatives through 3D bio-direct printing a promising clinical strategy for the treatment of tumor-
technology. Zhang et al. [145] used sodium alginate solution induced bone defects. Liu et al. [158] used Darvan821-A
as a printing ink and formed vascular-like structures as a size controlling agent and dispersant for the 1 time
st
through coaxial printing by physical cross-linking using during HA synthesis to prevent the formation of particle
calcium chloride solution. Compared to conventional aggregates throughout the COL matrix, resulting in COL-
scaffold structures with a 21% reduction in volume, nHA scaffolds with excellent rheological properties and
the lubricin gene PRG-4 also showed over a twofold great potential for precise tailoring of scaffold shape.
higher expression in hollow fibers after encapsulation of In addition, inhibition of tumor cell growth can also be
cartilage progenitor cells. achieved by incorporating materials with photothermal
properties in the scaffold to control temperature changes
4.3. Drug-carrying antibacterial under infrared irradiation. Wang et al. [159] prepared a series

Malignant bone tumors mainly include osteosarcoma, of black bioceramic powders with good biocompatibility
chondrosarcoma, and Ewing sarcoma [146-148] . At present, by magnesium thermal reduction, and the presence of
a combination of surgical resection, chemotherapy, and a large number of oxygen vacancies inside the crystals
radiotherapy is often used for malignant bone tumors, improved the degradation properties of the scaffold
and this treatment has significantly improved the overall materials and the adhesion effect for osteoblasts and skin
survival rate of patients in the last 5 years [149] . However, cells. Under low-power infrared irradiation, the black
surgical resection cannot completely eliminate tumor bioactive ceramic scaffolds demonstrated a significant
cells and can lead to bone defects, and chemotherapy photothermal warming effect, and the survival rate of
and radiotherapy may induce side effects such as drug LM8 cells was only 0.98% at 25 min after irradiation.
[160]
resistance and radiation resistance in normal tissues. Bo et al. combined copper ion-ligated meso-Tetra(4-
To address these long-standing challenges for patients, carboxyphenyl) porphine (Cu-TCPP) with tricalcium
researchers have worked to develop bone repair scaffolds phosphate ceramic scaffold material to make Cu-TCPP-
that have antimicrobial properties and inhibit the growth TCP composite scaffold, and based on the in vitro
of tumor cells. experiments on PTT, 20Cu-TCPP-TCP scaffold had only
Bioceramic materials are widely used in the repair 10% bone tumor cell activity under near-infrared light
of tissue defects in bone, teeth and skin due to their irradiation.
ability to induce tissue regeneration and regulate cell 5. Conclusions
growth and functional differentiation. In recent years,
it has been found that composite scaffolds made of In summary, this paper points out that the standard of
bioceramic materials and materials which containing bone repair scaffolds within the field of tissue engineering
tumor growth inhibitors can not only keep the growth of is getting higher. Conventional bone repair scaffolds can
tumor cells, but also further repair bone defects caused by no longer meet the high standards and requirements of
surgery [150-152] . Mehdi et al. [153] prepared a gelatin/β-TCP clinical applications in terms of preparation process and
composite scaffold, and in vivo experiments showed that service performance. A wide range of researchers are
the rate of new bone formation throughout the defective dedicated to exploring the diversity of scaffold structures
area was more than 75% after 3 – 4 months, the scaffold and functions and developing bioprinting technologies to
was further treated by adding zoledronic acid which improve the filament structure, material composition and
inhibits tumor cell growth and the gelatin/β-TCP scaffold scaffold functions in terms of printing paste, preparation
structure could modulate the release of drugs in vivo for process, and scaffold structure in order to build bone
therapeutic effect. repair scaffolds that meet modern clinical requirements.
In recent years, photothermal therapy (PTT), In terms of material composition, bioceramics as the
a minimally invasive and highly effective antitumor traditional bone repair scaffold material have been the
approach, has been shown in numerous clinical trials to first choice of researchers, but the unchanging ceramic
improve the effectiveness of tumor treatment and reduce scaffold cannot meet the clinical needs of contemporary
side effects [154-156] . PTT requires ablation of tumor tissue society. The introduction of polymeric materials has
by induced thermotherapy with the help of photothermal greatly improved the biocompatibility and printability
agents. Wang et al. [157] developed a new bifunctional of scaffolds. Some materials in polymers, such as
biomaterial (MS-AKT scaffold) with photothermal hydrogel, COL, and PLA, have good viscoelasticity
therapeutic ability and bone regeneration ability, and as well as biocompatibility, and it can be introduced

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