Synergistic antitumour effects of chemo-immunotherapy with an oxazaphosphorine drug and IL-2-secreting cells in a mouse colon cancer model

The therapeutic efficacies of two chemical agents-cyclophosphamide (CY) and compound CBM-11-were compared in a chemo-immunotherapy protocol combining a single injection of a cytotoxic agent with a series of weekly peritumoural (p.t.) administrations of non-tumourigenic plasmocytoma cells engineered to produce interleukin-2 (IL-2). Compound CBM-11, an optically active S(-) isomeric form of a bromine-substituted analogue of ifosfamide, is currently used in Phase I clinical trials in Poland. The treatment was applied to mice bearing well-established subcutaneous (s.c.) MC-38 colon tumours. Single intraperitoneal injection of 200 mg/kg of CY or of an equitoxic dose of 140 mg/kg of CBM-11 alone resulted in a tumour growth delay (TGD) of 10-13 and 17-21 d, respectively. This effect was accompanied by an increase in life-span (ILS) of at most 42 and 62% over control. Complete responses (CR) were not observed. Combination of CY or CBM-11 with 6-7 p.t. injections of IL-2-secreting cells resulted in potentiation of the therapeutic effects: TGD and ILS values were considerably increased and long-lasting CRs were observed. The overall incidence of CR after combined treatment was ca 16% and 42% for CY and CBM-11, respectively (P=0.049). A specific anti-MC-38 immunity was induced by the treatment, as verified by rechallenge of cured mice with MC-38 tumour cells 3-4 months post therapy cessation. Our results indicate that tumour destruction by chemotherapy (even if not complete) and prolonged local delivery of IL-2 secreted by allogeneic cells of an easy to culture line are sufficient to secure long-lasting specific antitumour immunity in cured mice.     

Chronic lymphocytic leukemia

Patients with purine analogue–refractory chronic lymphocytic leukemia (CLL) have short survival and limited treatment options. Defining the best salvage strategies for this population is challenging, because limited data are available from clinical trials, and because studies have enrolled mixed populations (patients with recurrent and refractory disease or patients with refractory disease and Richter transformation). Moreover, patients with refractory CLL have a high incidence of unfavorable molecular and clinical features, such as high‐risk genomic profiles, unmutated immunoglobulin heavy‐chain genes, expression of zeta‐chain–associated protein kinase 70, and bulky lymphadenopathies. These patients are also severely immunosuppressed because of the underlying disease and the treatments received, and experience a high rate of infectious complications that pose an additional difficulty in selecting treatment. Despite these challenges, in parallel with better characterizations of the biologic features of refractory CLL, the number of available treatment modalities for this population has increased. Several chemoimmunotherapy combinations have been developed, and novel agents with a different mechanism of action are being investigated in clinical trials. Furthermore, allogeneic stem cell transplantation with nonmyeloablative conditioning regimens is a therapeutic strategy that is increasingly offered to patients with refractory CLL. Cancer 2009. © 2009 American Cancer Society.     

Supplementary granulocyte macrophage colony‐stimulating factor to chemotherapy and programmed death‐ligand 1 blockade decreases local recurrence after surgery in bladder cancer

Despite advances and refinements in surgery and perioperative chemotherapy, there are still unmet medical needs with respect to radical cystectomy for muscle‐invasive bladder cancer (MIBC). We investigated the potential benefit of supplementary granulocyte macrophage colony‐stimulating factor (GM‐CSF) to chemoimmunotherapy with programmed cell death protein‐1 (PD‐1)/programmed death‐ligand 1 (PD‐L1) axis blockade and standard neoadjuvant chemotherapy in bladder cancer. We inoculated 2 × 10⁵ MBT2 cells s.c. in C3H mice to create a syngeneic animal model of local recurrence (LR). When the tumor diameter reached 12 mm, the mice were allocated randomly as follows: (i) non‐treated control (vehicle only); (ii) anti‐mPD‐L1 monotherapy; (iii) mGM‐CSF monotherapy; (iv) anti‐mPD‐L1 plus mGM‐CSF; (v) gemcitabine and cisplatin (GC); (vi) GC plus anti‐mPD‐L1; (vii) GC plus mGM‐CSF; and (viii) GC plus anti‐mPD‐L1 plus mGM‐CSF. After completing 2‐week neoadjuvant therapy, tumors were resected for resection margin evaluation and immunohistochemical staining and blood was collected for flow cytometry and ELISA. Operative wounds were sutured, and the operative site was monitored to detect LR. Addition of anti‐mPD‐L1 and mGM‐CSF to neoadjuvant GC chemotherapy enhanced the antitumor effect and reduced positive resection margins (50% vs 12.5%). Combination of GC, anti‐mPD‐L1, and mGM‐CSF resulted in longer LR‐free survival and cancer‐specific survival compared to those in other groups. These effects involved an immunotherapy‐related decrease in oncological properties such as tumor invasion capacity and epithelial‐mesenchymal transition. mGM‐CSF significantly decreased the accumulation of myeloid‐derived suppressor cells in both the blood and tumor microenvironment and blood interleukin‐6 levels. Supplementary GM‐CSF to neoadjuvant GC plus PD‐L1 blockade could decrease LR after radical surgery by immune modulation in the blood and tumor microenvironment.     

A trial of adjuvant combination chemoimmunotherapy for stage III carcinoma of stomach

A chemoimmunotherapy program designed on the basis of experimental results was administered to 27 patients with stage III carcinoma of stomach following curative resection. The treatment regimen consisted of active immunotherapy with Vibrio cholerae neuraminidase (VCN)-treated autologous tumor cells admixed with bacillus Calmette-Guérin (BCG) and chemotherapy with drugs such as cyclophosphamide (CY), mitomycin C (MMC), and 5-fluorouracil (FU) which proved to enhance the immune response when administered at optimal dose and timing. Then, it was followed by long-term administration of tegafur (FT) and immunomodulators. This treatment significantly improved survival when compared to that of 41 historical control patients treated with surgery alone (P less than 0.001). As compared to 31 control patients concurrently treated with a bolus dose of MMC followed by long-term FT and immunomodulators, survival had a tendency, but not significantly, to be improved in patients treated with this therapy (P less than 0.1). However, the survival rate at 4.5 years was significantly higher than that of control patients (P less than 0.01). These results appeared to show that this type of adjuvant combination chemoimmunotherapy may be of benefit for this group of patients with gastric carcinoma.     

Immunotherapy options in metastatic renal cell cancer: where we are and where we are going

The treatment of renal cell carcinoma is rapidly changing as a result of recent evidence concerning the efficacy of biological drugs, antiangiogenetic agents and signal-transduction inhibitors. This paper will provide a critical overview of the use of immunotherapy in renal cell carcinoma and review the available data concerning the efficacy of interferons, interleukin-2 and other forms of immunological treatment, particularly allogenic transplantation and vaccines. Moreover, it will focus on the new mechanisms of regulation of the immune system with a better understanding of the interaction between host and tumor, the role of T regulatory cells, heat-shock proteins and vaccines. The mechanism of action and the results obtained in renal cell carcinoma using the new molecular targeted drugs will be examined, along with the possibility of using immunotherapy combined with the new biological agents. Future research will not only need to make every effort to optimize the use of the new molecules and to define their efficacy precisely, but also to consider how to integrate these drugs with the traditional immunotherapy.     

Neoadjuvant pembrolizumab with chemotherapy for the treatment of stage IIB–IIIB resectable lung squamous cell carcinoma

BackgroundResearches on programmed cell death (PD-1) as neoadjuvant immunotherapy for resectable non-small cell lung cancer is underway, which brings hope for individuals with the disease. However, a study dedicated to lung squamous cell carcinoma (LUSC) specifically has yet to be conducted. Now, data from our pilot prospective research neoadjuvant study provide new insights in the field of neoadjuvant regimen for LUSC.MethodsBetween June 2019 and July 2020, 37 adults with untreated, surgically resectable stage IIB–IIIB LUSC were enrolled into this prospective study. Patients received 2 cycles of pembrolizumab (2 mg/kg) with chemotherapy (albumin-bound paclitaxel 100 mg/m² on days 1 and 8 + carboplatin AUC 5) via intravenous administration every 3 weeks, and underwent surgical treatment 3–4 weeks after the second cycle. The primary endpoint of the study was the tumor pathologic complete response (pCR) rate. The toxicity profile, tumor major pathological remission, complete resection rate, response rate, and operative and postoperative complications were also evaluated.ResultsThe postoperative pathological specimens of 17 (45.9%) patients suggested pCR. Neoadjuvant pembrolizumab with chemotherapy had an acceptable side-effect profile, and no patients withdrew from the study preoperatively due to disease progression or toxicity. A major pathological response occurred in 24 (64.9%) resected tumors. All tumors were completely resected (R0, 100%). According to the Response Evaluation Criteria in Solid Tumors (RESIST), a response was evaluated before surgery in 32 (86.5%) patients by computed tomography. Twenty-five (67.6%) patients underwent thoracoscopic surgery. No deaths or postoperative major complications requiring reoperation occurred. Recurrence or metastasis was found in 2 patients during follow-up of 2–14 months.ConclusionsThe early outcomes of pembrolizumab with chemotherapy in the neoadjuvant setting as a novel treatment for resectable stage IIB–IIIB LUSC showed a high pCR rate that has not been seen previously, as well as a high R0 resection rate and a low toxicity profile. The long-term efficacy of this novel treatment and the validity of the present findings should be confirmed with longer follow-up and prospective comparative trials.