[Intratumoral chemotherapy: experimental data and applications to head and neck tumors]

Ropivacaine-loaded hydrogels for prolonged relief of chemotherapy-induced peripheral neuropathic pain and potentiated chemotherapy

Chemotherapy can cause severe pain for patients, but there are currently no satisfactory methods of pain relief. Enhancing the efficacy of chemotherapy to reduce the side effects of high-dose chemotherapeutic drugs remains a major challenge. Moreover, the treatment of chemotherapy-induced peripheral neuropathic pain (CIPNP) is separate from chemotherapy in the clinical setting, causing inconvenience to cancer patients. In view of the many obstacles mentioned above, we developed a strategy to incorporate local anesthetic (LA) into a cisplatin-loaded PF127 hydrogel for painless potentiated chemotherapy. We found that multiple administrations of cisplatin-loaded PF127 hydrogels (PFC) evoked severe CIPNP, which correlated with increased pERK-positive neurons in the dorsal root ganglion (DRG). However, incorporating ropivacaine into the PFC relieved PFC-induced CIPNP for more than ten hours and decreased the number of pERK-positive neurons in the DRG. Moreover, incorporating ropivacaine into the PFC for chemotherapy is found to upregulate major histocompatibility complex class I (MHC-I) expression in tumor cells and promote the infiltration of cytotoxic T lymphocytes (CD8+ T cells) in tumors, thereby potentiating chemotherapy efficacy. This study proposes that LA can be used as an immunemodulator to enhance the effectiveness of chemotherapy, providing new ideas for painless cancer treatment.

Resensitization to Nivolumab after Intratumoral Chemotherapy in Recurrent Head and Neck Squamous Cell Cancer: A Report of 2 Cases

The survival of patients with head and neck squamous cancer with locoregional recurrence is short if salvage surgery or radiation cannot be performed. Systemic chemotherapy based on platinum salts and cetuximab produces only partial and transient responses. Immune checkpoint inhibitors (i.e., nivolumab) lead to a low complete response rate of only about 10%, but in some cases the effects can be long-lasting. Intratumoral chemotherapy (ITC) has been proposed for patients with local recurrence of head and neck squamous cell carcinoma with an objective response rate of 27-50%. However, it often leads to peritumoral tissue necrosis, and the duration of local control is limited. Here, we present 2 patients with head and neck squamous cell cancer whose local recurrences were refractory to intravenous chemotherapy and nivolumab. ITC using nonnecrotizing molecules, associated with nivolumab, led to complete stable local and distant response. ITC seems to trigger tumor resensitization to previously ineffective immunotherapy. This combination deserves an evaluation in the framework of a prospective trial.

Organ-based drug delivery

The phenomenal advances in pharmaceutical sciences over the last few decades have led to the development of new therapeutics like peptides, proteins, RNAs, DNAs and highly potent small molecules. Fruitful applications of these therapeutics have been challenged by several anatomical and physiological barriers that limit adequate drug disposition at the site-of-action and by off-target drug distribution to undesired tissues, which together result in the reduced effectiveness and increased side effects of therapeutic agents. As such, the development of drug delivery and targeting systems has been recognised as a cornerstone for future drug development. Research in pharmaceutical sciences is now devoted to tackling delivery challenges through engineering delivery systems that move beyond conventional dosage forms and regimens into state-of-the-art targeted drug delivery tailored toward specific therapeutic needs. Modern drug delivery systems comprise passive and active targeting approaches. While passive targeting relies on the natural course of distribution of drugs or drug carriers in the body, as governed by their physicochemical properties, active targeting often exploits targeting moieties that home preferentially into target tissues. Here, we provide an overview of theories of and approaches to passive and active drug delivery. As the design of drug delivery is dependent on the unique structure of target tissues and organs, we present our discussion in an organ-specific manner with the aim to inspire the development of new strategies for curing disease with high accuracy and efficiency.

N-Butyl-2-cyanoacrylate-based injectable and in situ-forming implants for efficient intratumoral chemotherapy

The local delivery of chemotherapeutic drugs to tumor sites is an effective approach for achieving therapeutic drug concentrations in solid tumors. Injectable implants with the ability to form in situ represent one of the most promising technologies for intratumoral chemotherapy. However, many issues must be resolved before these implants can be applied in clinical practice. Herein, we report a novel injectable in situ-forming implant system composed of n-butyl-2-cyanoacrylate (NBCA) and ethyl oleate, and the sol–gel phase transition is activated by anions in body fluids or blood. This newly developed injectable NBCA ethyl oleate implant (INEI) is biodegradable, biocompatible, and non-toxic. INEI solidifies in several seconds after exposure to body fluids or blood, and the implant’s in vivo degradation time can be controlled. In addition, the pore sizes formed by the polymerization of NBCA can be decreased by increasing the NBCA concentration in the implants. Therefore, the drug retention/release time can be adjusted from a few weeks to several months by changing the concentration of NBCA in the implant formulation. Anti-tumor experiments in animal models showed that the average growth inhibition rate of xenografted human breast cancer cells by the paclitaxel-loaded INEI (40% NBCA) was 80%, and they also indicated that tumors in some of the mice were completely eliminated by just a single dosage injection. For the epirubicin-loaded INEI (50% NBCA), the average growth inhibition rate of xenografted human liver cancer cells was 58%. Thus, the chemotherapeutic drug-loaded INEIs exhibited excellent therapeutic efficacy for local chemotherapy.

Antiangiogenesis enhances intratumoral drug retention

The tumor vasculature delivers nutrients, oxygen, and therapeutic agents to tumor cells. Unfortunately, the delivery of anticancer drugs through tumor blood vessels is often inefficient and can constitute an important barrier for cancer treatment. This barrier can sometimes be circumvented by antiangiogenesis-induced normalization of tumor vasculature. However, such normalizing effects are transient; moreover, they are not always achieved, as shown here, when 9L gliosarcoma xenografts were treated over a range of doses with the VEGF receptor-selective tyrosine kinase inhibitors axitinib and AG-028262. The suppression of tumor blood perfusion by antiangiogenesis agents can be turned to therapeutic advantage, however, through their effects on tumor drug retention. In 9L tumors expressing the cyclophosphamide-activating enzyme P450 2B11, neoadjuvant axitinib treatment combined with intratumoral cyclophosphamide administration significantly increased tumor retention of cyclophosphamide and its active metabolite, 4-hydroxycyclophosphamide. Similar increases were achieved using other angiogenesis inhibitors, indicating that increased drug retention is a general response to antiangiogenesis. This approach can be extended to include systemic delivery of an anticancer prodrug that is activated intratumorally, where antiangiogenesis-enhanced retention of the therapeutic metabolite counterbalances the decrease in drug uptake from systemic circulation, as exemplified for cyclophosphamide. Importantly, the increase in intratumoral drug retention induced by neoadjuvant antiangiogenic drug treatment is shown to increase tumor cell killing and substantially enhance therapeutic activity in vivo. Thus, antiangiogenic agents can be used to increase tumor drug exposure and improve therapeutic activity following intratumoral drug administration, or following systemic drug administration in the case of a therapeutic agent that is activated intratumorally.

Direct intratumoral chemotherapy with carboplatin and epinephrine in a recurrent cervical chordoma: case report

OBJECTIVE

Chordomas are rare primary bone tumors for which surgery is classically the first-line treatment. However, safe margins are often difficult to obtain, so that patients are at risk of local recurrence. Because radiation therapy and systemic chemotherapy show limited effectiveness, we report the use of direct intratumoral chemotherapy (IC) to treat recurrent chordoma.

CLINICAL PRESENTATION

A 46-year-old man presented with a recurrent cervical chordoma after surgery and radiation therapy. This recurrence manifested as C4-C5 spinal cord compression.

TECHNIQUE

Three 22-gauge needles were inserted at the upper, middle, and lower parts of the tumor and advanced under computed tomographic guidance while injecting local anesthetic. A 5-mg/mL carboplatin solution was combined with epinephrine (to increase the concentration and antitumor effect of carboplatin) at a final concentration of 0.01 mg/mL and an iodinated contrast agent. We injected 3 to 5 mL of this solution over 5 minutes through each needle under computed tomographic guidance. Eleven intratumoral treatments were performed during an 18-month period.

CONCLUSION

A marked clinical response with regression of the spinal cord compression was observed, without specific toxicity. A good partial response was obtained with a 42% decrease in tumor volume (from 69 to 40 cm3). Moreover, the central part of the tumor showed tumor necrosis, as confirmed by histological examination. Thus, in patients with this rare tumor, intratumoral chemotherapy may be a valid treatment option when surgery and radiation therapy fail. Furthermore, intratumoral chemotherapy in combination with surgical treatment should be considered to improve the local control rate.

Cationic liposomes loaded with proapoptotic peptide D-(KLAKLAK)(2) and Bcl-2 antisense oligodeoxynucleotide G3139 for enhanced anticancer therapy

The treatment of cancer using macromolecular therapeutics such as oligonucleotides or peptides requires efficient delivery systems capable of intracellular penetration and may also benefit from use of a combination of therapeutics with different mechanisms of action. With this possibility in mind, we constructed cationic liposome loaded with the proapoptotic peptide, d-(KLAKLAK)(2) and the Bcl-2 antisense oligodeoxynucleotide, G3139, and determined whether the combination of the proapoptotic macromolecules in a single cationic liposome can enhance antitumor efficacy. Advantage was taken of alternating charge interaction to entrap macromolecules of opposite charge. The polycationic peptide d-(KLAKLAK)(2) was first condensed with the polyanionic oligodeoxynucleotide G3139 to obtain overall negatively charged peptide/oligodeoxynucleotide complexes. The complexes were then entrapped into DOTAP/DOPE cationic liposomes (CL). This sequential charge interaction ensured efficient entrapment of d-(KLAKLAK)(2) and G3139 with a high loading efficiency (50%) and capacity (7.5 wt %). In vitro treatment of mouse melanoma B16(F10) with CL loaded with d-(KLAKLAK)(2)/G3139 led to significantly enhanced antitumor efficacy, mediated by stimulated induction of apoptotic (caspase 3/7) activity, when compared to CL loaded with G3139 alone. Intratumoral injection of CL loaded with d-(KLAKLAK)(2)/G3139 in B16(F10) mice xenograft also led to suppressed tumor growth associated with enhanced apoptotic activity. Thus, the combination of proapoptotic peptide d-(KLAKLAK)(2) and antisense oligonucleotide G3139 in a cationic liposome led to enhanced apoptotic/antitumor efficacy and may provide a promising tool for cancer treatment.

Potentiation of methoxymorpholinyl doxorubicin antitumor activity by P450 3A4 gene transfer

Preclinical and clinical studies of CYP gene-directed enzyme prodrug therapy have been focused on anticancer prodrugs activated by CYP2B enzymes, which have low endogenous expression in human liver; however, the gene therapeutic potential of CYP3A enzymes, which are highly expressed in human liver, remains unknown. This study investigated methoxymorpholinyl doxorubicin (MMDX; nemorubicin), a novel CYP3A-activated anticancer prodrug. Retroviral transfer of CYP3A4 increased 9L gliosarcoma cell chemosensitivity to MMDX 120-fold (IC(50)=0.2 nM in 9L/3A4 cells). In CHO cells, overexpression of P450 reductase in combination with CYP3A4 enhanced chemosensitivity to MMDX, and to ifosfamide, another CYP3A4 prodrug, 11- to 23-fold compared with CYP3A4 expression alone. CYP3A4 expression and MMDX chemosensitivity were increased in human lung (A549) and brain (U251) tumor cells infected with replication-defective adenovirus encoding CYP3A4. Coinfection with Onyx-017, a replication-conditional adenovirus that coamplifies and coreplicates the Adeno-3A4 virus, led to large increases in CYP3A4 RNA but only modest increases in CYP3A4 protein and activity. MMDX induced remarkable growth delay of 9L/3A4 tumors, but not the P450-deficient parental 9L tumors, in immunodeficient mice administered low-dose MMDX either intravenous or by direct intratumoral (i.t.) injection (60 microg kg(-1), every 7 days x 3). Notably, the i.t. route was substantially less toxic to the mouse host. No antitumor activity was observed with intraperitoneal MMDX treatment, suggesting a substantial hepatic first pass effect, with activated MMDX metabolites formed in the liver having poor access to the tumor site. These studies demonstrate that human CYP3A4 has strong potential for MMDX prodrug-activation therapy and suggest that endogenous tumor cell expression of CYP3A4, and not hepatic CYP3A4 activity, is a key determinant of responsiveness to MMDX therapy in cancer patients in vivo.