Long-lasting complete remission in a patient with systemic metastases of recurrent breast cancer treated with cyclin-dependent kinases 4/6 inhibitors: a case report.

BACKGROUND: The prognosis for recurrence cases of hormone receptor-positive HER2-negative breast cancer remains poor, and treatment strategies that emphasize quality of life have often been chosen, with few physicians aiming for a cure. Our objective is to assess the validity of such current treatment strategies. CASE PRESENTATION: A 74-year-old Asian woman with multiple lung and liver metastases after local recurrence of breast cancer was treated with two different cyclin-dependent kinases 4/6 inhibitors sequentially in combination with endocrine therapy. Flow cytometric analysis of the patient's peripheral blood mononuclear cells was also performed to evaluate the host's immune status. Complete remission was achieved without cytotoxic agents and the patient remains disease free to this day, 6 years after the initial relapse. Additionally, no increase in the population of the immunosenescent T cells with a phenotype of CD8+CD28- was observed in the patient's peripheral blood mononuclear cells, suggesting that the immune system was well maintained. CONCLUSIONS: We present this case study to develop new treatment strategies for recurrent breast cancer that is not only bound to misinterpretations of the Hortobagyi algorithm, but also aim for a cure with noncytotoxic agents to maintain the host's immune system and early detection of recurrence.

Potent antitumor effects of the conditioned medium of bone marrow-derived mesenchymal stem cells via IGFBP-4.

Cell transfer therapy using mesenchymal stem cells (MSCs) has pronounced therapeutic potential, but concerns remain about immune rejection, emboli formation, and promotion of tumor progression. Because the mode of action of MSCs highly relies on their paracrine effects through secretion of bioactive molecules, cell-free therapy using the conditioned medium (CM) of MSCs is an attractive option. However, the effects of MSC-CM on tumor progression have not been fully elucidated. Herein, we addressed this issue and investigated the possible underlying molecular mechanisms. The CM of MSCs derived from human bone marrow greatly inhibited the in vitro growth of several human tumor cell lines and the in vivo growth of the SCCVII murine squamous cell carcinoma cell line with reduced neovascularization. Exosomes in the MSC-CM were only partially involved in the inhibitory effects. The CM contained a variety of cytokines including insulin-like growth factor binding proteins (IGFBPs). Among them, IGFBP-4 greatly inhibited the in vitro growth of these tumors and angiogenesis, and immunodepletion of IGFBP-4 from the CM significantly reversed these effects. Of note, the CM greatly reduced the phosphorylation of AKT, ERK, IGF-1 receptor beta, and p38 MAPK in a partly IGFBP4-dependent manner, possibly through its binding to IGF-1/2 and blocking the signaling. The CM depleted of IGFBP-4 also reversed the inhibitory effects on in vivo tumor growth and neovascularization. Thus, MSC-CM has potent inhibitory effects on tumor growth and neovascularization in an IGFBP4-dependent manner, suggesting that cell-free therapy using MSC-CM could be a safer promising alternative for even cancer patients.

Induction of potent antitumor immunity by intradermal DNA injection using a novel needle-free pyro-drive jet injector.

The current success of mRNA vaccines against COVID-19 has highlighted the effectiveness of mRNA and DNA vaccinations. Recently, we demonstrated that a novel needle-free pyro-drive jet injector (PJI) effectively delivers plasmid DNA into the skin, resulting in protein expression higher than that achieved with a needle syringe. Here, we used ovalbumin (OVA) as a model antigen to investigate the potential of the PJI for vaccination against cancers. Intradermal injection of OVA-expression plasmid DNA into mice using the PJI, but not a needle syringe, rapidly and greatly augmented OVA-specific CD8+ T-cell expansion in lymph node cells. Increased mRNA expression of both interferon-γ and interleukin-4 and an enhanced proliferative response of OVA-specific CD8+ T cells, with fewer CD4+ T cells, were also observed. OVA-specific in vivo killing of the target cells and OVA-specific antibody production of both the IgG2a and IgG1 antibody subclasses were greatly augmented. Intradermal injection of OVA-expression plasmid DNA using the PJI showed stronger prophylactic and therapeutic effects against the progression of transplantable OVA-expressing E.G7-OVA tumor cells. Even compared with the most frequently used adjuvants, complete Freund's adjuvant and aluminum hydroxide with OVA protein, intradermal injection of OVA-expression plasmid DNA using the PJI showed a stronger CTL-dependent prophylactic effect. These results suggest that the novel needle-free PJI is a promising tool for DNA vaccination, inducing both a prophylactic and a therapeutic effect against cancers, because of prompt and strong generation of OVA-specific CTLs and subsequently enhanced production of both the IgG2a and IgG1 antibody subclasses.

A patient with stage IIIB advanced breast cancer who is still alive 24 years after surgery: a case report and remarks on the treatment strategies.

Background: In recent years, a number of agents possessing novel mechanisms, such as cyclin-dependent kinase 4/6 (CDK 4/6) inhibitors and PIK3CA inhibitors, have been developed for the treatment of hormone receptor-positive (HR+) human epidermal growth factor receptor type negative (HER2-) advanced or recurrent breast cancer. As a result, the treatment strategies for advanced or recurrent breast cancer have changed significantly. The combination of CDK 4/6 inhibitors administration and endocrine therapy is now widely used in the treatment of HR+ HER2- recurrent breast cancer with improved outcomes. In 2021, abemaciclib was approved as post-operative adjuvant combination therapy with endocrine therapy for HR+ HER2- advanced breast cancer and is expected to suppress postoperative recurrence. A range of new agents are being developed in addition to CDK4/6 inhibitors that provided more options of treatment strategies for advanced or recurrent breast cancer, which in turn could improve outcomes. However, the prognosis for the recurrent HR+ HER2- breast cancer remains poor, overall survival (OS) is still very low and a complete cure is difficult even with the treatments. Case Description: In 1998, 24 years ago, neoadjuvant chemotherapy (NAC) and the concept of subtypes were not even widespread, the number of available drugs was far fewer than today, the clinical treatment guidelines had not been established. Nevertheless, we experienced a case of HR+ HER2- advanced breast cancer, stage IIIB at the initial diagnosis, which was consistently treated with the aim of complete cure and with the various treatments available at the time, resulting in long-term survival. 24 years have passed since the initial surgery, the patient has continued to do well despite repeated recurrences and remissions. Conclusions: We report here a case of long-term survival in advanced breast cancer of 24 years after surgery, and remark for future treatment strategies that not bound by the conventional treatment policy that emphasizes quality of life without aiming for complete cure.

A Chaperone-Like Role for EBI3 in Collaboration With Calnexin Under Inflammatory Conditions.

The interleukin-6 (IL-6)/IL-12 family of cytokines plays critical roles in the induction and regulation of innate and adaptive immune responses. Among the various cytokines, only this family has the unique characteristic of being composed of two distinct subunits, α- and ß-subunits, which form a heterodimer with subunits that occur in other cytokines as well. Recently, we found a novel intracellular role for one of the α-subunits, Epstein-Barr virus-induced gene 3 (EBI3), in promoting the proper folding of target proteins and augmenting its expression at the protein level by binding to its target protein and a well-characterized lectin chaperone, calnexin, presumably through enhancing chaperone activity. Because calnexin is ubiquitously and constitutively expressed but EBI3 expression is inducible, these results could open an avenue to establish a new paradigm in which EBI3 plays an important role in further increasing the expression of target molecules at the protein level in collaboration with calnexin under inflammatory conditions. This theory well accounts for the heterodimer formation of EBI3 with p28, and probably with p35 and p19 to produce IL-27, IL-35, and IL-39, respectively. In line with this concept, another ß-subunit, p40, plays a critical role in the assembly-induced proper folding of p35 and p19 to produce IL-12 and IL-23, respectively. Thus, chaperone-like activities in proper folding and maturation, which allow the secretion of biologically active heterodimeric cytokines, have recently been highlighted. This review summarizes the current understanding of chaperone-like activities of EBI3 to form heterodimers and other associations together with their possible biological implications.

IL-23p19 and CD5 antigen-like form a possible novel heterodimeric cytokine and contribute to experimental autoimmune encephalomyelitis development.

Among various cytokines, interleukin (IL)-12 family cytokines have very unique characteristics in that they are composed of two distinct subunits and these subunits are shared with each other. IL-23, one of the IL-12 family cytokines, consists of p19 and p40 subunits, is mainly produced by antigen-presenting cells, and plays a critical role in the expansion and maintenance of pathogenic helper CD4+ T (Th)17 cells. Since we initially found that p19 is secreted in the culture supernatant of activated CD4+ T cells, we have further investigated the role of p19. p19 was revealed to associate with CD5 antigen-like (CD5L), which is a repressor of Th17 pathogenicity and is highly expressed in non-pathogenic Th17 cells, to form a composite p19/CD5L. This p19/CD5L was shown to activate STAT5 and enhance the differentiation into granulocyte macrophage colony-stimulating factor (GM-CSF)-producing CD4+ T cells. Both CD4+ T cell-specific conditional p19-deficient mice and complete CD5L-deficient mice showed significantly alleviated experimental autoimmune encephalomyelitis (EAE) with reduced frequency of GM-CSF+CD4+ T cells. During the course of EAE, the serum level of p19/CD5L, but not CD5L, correlated highly with the clinical symptoms. Thus, the composite p19/CD5L is a possible novel heterodimeric cytokine that contributes to EAE development with GM-CSF up-regulation.

Case report: two cases of extremely rare primary pure squamous cell carcinoma of the breast.

RATIONALE: Since primary pure squamous cell carcinoma of the breast is a rare disease, few reports describe the characteristic findings on performing preoperative imaging that can be used to distinguish it from normal breast cancer. The rapid evolution and lack of an established method of treatment has resulted in several reports of advanced cases of primary pure squamous cell carcinoma of the breast. PATIENT CONCERNS: Case 1 was a 44-year-old woman with an elastic, hard tumor in the left C region. Ultrasonographic analysis revealed a maximal 11-mm hypoechoic area. Histologically, the tumor was a well-differentiated squamous cell carcinoma with prominent keratinization, and there was prominent inflammatory cell infiltration, necrosis, and fibrosis. Case 2 was a 58-year-old woman with an elastic, hard tumor in the left C/D region. Ultrasonographic analysis revealed a maximal 31-mm hypoechoic area with partially calcified areas and a hyperechoic margin. Histologically, the tumor was a squamous cell carcinoma with prominent keratinization exhibiting an infiltrative growth pattern. The tumor had no connection to the epidermis and partially transitioned into the atypical ductal epithelium in the area surrounding the focus. DIAGNOSES: The patient in Case 1 was preoperatively diagnosed with T1cN0M0 Stage I cancer of the left breast, but both patients were finally diagnosed with T2N0M0 Stage IIA cancer. INTERVENTIONS: Case 1: left partial mastectomy and axillary lymph node dissection were performed. The patient was administered 4 courses of FEC100 and 4 courses of DTX as postoperative adjuvant therapy. Case 2: left modified radical mastectomy and axillary lymph node dissection were performed without any postoperative adjuvant therapy. OUTCOMES: Case 1: no sign of relapse was observed, but the patient moved away from the area to another hospital in March 2014 and eventually died due to relapse in January 2016. Case 2: four years after surgery, no relapse has been observed. LESSONS: We should always keep the presence of primary pure squamous cell carcinoma among breast cancers in mind although the crisis rate is very low. Due to its high malignancy, needle biopsy and aspiration biopsy cytology should be performed to make a definitive diagnosis.

[A case of peritoneal dissemination caused by recurrent hilar cholangiocarcinoma treated with intraperitoneal infusion of cisplatin (CDDP) and systemic chemotherapy].

Six years and 9 months ago, a 72-year-old man underwent left hepatectomy for a hilar cholangiocarcinoma(T2N0M0: Stage II A). At 3 years and 2 months after surgery, he was admitted for rectal tumor and reoperation. From surgery, it was diagnosed as peritoneal metastases of the cholangiocarcinoma, and an intraperitoneal infusion port was placed. He was treated with gemcitabine administered iv at day 1 and CDDP ip at day 8 every 3 or 4 weeks for 2 years. Then, gemcitabine was changed to docetaxel because of elevation of CA19-9. Both docetaxel iv and CDDP ip were administered for one and half years. For 3 years and 4 months, 12.2 g of CDDP, 28.0 g of gemcitabine and 920 mg of docetaxel were administered. As serum CA19-9 elevated again, he has been treated with S-1 and docetaxel ip for 3 months. This case indicates that intraperitoneal application of CDDP with systematic chemotherapy was effective for carcinomatous peritonitis without serious side effects.

[A case of pericardial tamponade caused by recurrent breast cancer treated with intrapericardial and intrapleural infusion of cisplatin (CDDP)].

Breast cancer rarely metastasizes to the pericardial cavity to cause cardiac tamponade. We have recently experienced a case of pericardial tamponade due to recurrent breast cancer. A 41-year-old woman who underwent modified radical mastectomy for a right breast cancer (T(1)N(3)M(0), Stage IIIA) 8 years and 8 months ago, was admitted for dyspnea and cough. Chest X-ray and CT scan revealed cardiomegaly and right pleural effusion, and cardiac echogram showed marked retention of pericardial effusion. A diagnosis of cardiac tamponade was made, and pericardiocentesis and thoracentesis were carried out immediately. Based on cytodiagnosis of pericardial and pleural effusion, the diagnosis was pericardial and intrapleural metastases of the breast cancer. Dyspnea was improved by pericardiocentesis and thocacentesis. Both intrapericardiac and intrathoracic instillation of CDDP prevented reaccumulation of pericardial and pleural effusion. After local chemotherapy with CDDP, systemic chemotherapy of CPT-11 was started. Thereafter the patient was discharged from the hospital and recovered her daily activities. This case indicates that intrapericardiac application of CDDP was effective for carcinomatous cardiac tamponade without serious side effects.

[A patient with recurrent gallbladder cancer responding to chemotherapy with CDDP/CPT-11 and gemcitabine].

A 79-year-old female patient was referred to our hospital for treatment of a recurrent gallbladder cancer. Before admission, she had undergone expanded cholecystectomy and had been treated successfully with 5-FU for 3 years to suppress the tumor growth in intraperitoneal lymph nodes. The recurrence of the tumor in lymph nodes near the pancreas head was demonstrated by computer tomography. We tried a course of a combination chemotherapy consisting of CPT-11 and CDDP (40 mg CPT-11/body/day on day 1 and 10 mg CDDP/body/day on day 2-5) to reduce the size of the nodes. Then, we repeated a total of 8 courses of the therapy at 4-week intervals. The status of the nodes was not changed for a year. Then, the lymph node started to enlarge again and obstructive jaundice appeared. So, we substituted gemcitabine (1 g/body/day) for the combination chemotherapy with expandable metallic stent implantation to drain the bile. As a result, metastatic lymph nodes were reduced in size and the dilatation of the interhepatic bile duct disappeared. Thereafter, the patient was given an additional 20 courses of gemcitabine therapy at 2-week intervals as an outpatient. No change was observed in the size of the metastatic lymph nodes for a year. However, the patient died of liver metastasis 8 years after operation and 6 years after she started chemotherapy for the recurrence. She maintained a good quality of life during that time. The present case suggests that combination of chemotherapy protocols is effective for clinical management of gallbladder cancer recurrence, which is generally considered to be difficult to manage with chemotherapy.

Synergistic antitumor effect by coexpression of chemokine CCL21/SLC and costimulatory molecule LIGHT.

To establish a more efficient treatment for immunotherapy against solid tumors, we have evaluated the antitumor effect by coexpression of a chemokine CCL21/secondary lymphoid tissue chemokine and a costimulatory molecule LIGHT in colon carcinoma C26. C26 cells expressing either CCL21 or LIGHT exhibited a significantly reduced tumor growth in vivo, and mice inoculated with these cells showed a prolonged survival, but eventually all these mice died. In contrast, C26 cells expressing both CCL21 and LIGHT exhibited a minimal tumor growth in vivo, and all these mice survived healthily with a tumor remission and consequently acquired a strong protective immunity. A markedly increased infiltration of mature dendritic cells (DCs), and CD8(+) T cells was observed in the tumor mass, and their spleen cells showed a greatly enhanced cytotoxic T lymphocyte (CTL) activity against C26 tumor and interferon (IFN)-gamma production. Neutralization of IFN-gamma or depletion of CD8(+) or CD4(+) T cells significantly reduced the antitumor activity. These results suggest that the combined treatment with CCL21 and LIGHT is able to induce a synergistic antitumor effect to eradicate tumor completely by greatly enhancing tumor-infiltration of lymphocytes including mature DCs and CD8(+) T cells, resulting in markedly augmented CTL activity and IFN-gamma production.